Title: Fluent form not working Last modified: April 8, 2026 --- # Fluent form not working * [rosejoydigital](https://wordpress.org/support/users/rosejoydigital/) * (@rosejoydigital) * [4 days, 14 hours ago](https://wordpress.org/support/topic/fluent-form-not-working/) * my fluet form stop working and is showing this: * **Fatal error**: Uncaught Error: Call to undefined function FluentForm\Framework\ Support\mb_strtoupper() in /home/mrsclean/public_html/wp-content/plugins/fluentform/ vendor/wpfluent/framework/src/WPFluent/Support/Str.php:1318 Stack trace: #0 / home/mrsclean/public_html/wp-content/plugins/fluentform/vendor/wpfluent/framework/ src/WPFluent/Support/Str.php(1720): FluentForm\Framework\Support\Str::upper()# 1 /home/mrsclean/public_html/wp-content/plugins/fluentform/vendor/wpfluent/framework/ src/WPFluent/Support/Str.php(1580): FluentForm\Framework\Support\Str::ucfirst()# 2 [internal function]: FluentForm\Framework\Support\Str::FluentForm\Framework\ Support\{closure}() #3 /home/mrsclean/public_html/wp-content/plugins/fluentform/ vendor/wpfluent/framework/src/WPFluent/Support/Str.php(1579): array_map() #4 / home/mrsclean/public_html/wp-content/plugins/fluentform/vendor/wpfluent/framework/ src/WPFluent/Database/Orm/Concerns/HasAttributes.php(613): FluentForm\Framework\ Support\Str::studly() #5 /home/mrsclean/public_html/wp-content/plugins/fluentform/ vendor/wpfluent/framework/src/WPFluent/Database/Orm/Concerns/HasAttributes.php( 2024): FluentForm\Framework\Database\Orm\Model->hasGetMutator() #6 /home/mrsclean/ public_html/wp-content/plugins/fluentform/vendor/wpfluent/framework/src/WPFluent/ Database/Orm/Concerns/HasAttributes.php(500): FluentForm\Framework\Database\Orm\ Model->transformModelValue() #7 /home/mrsclean/public_html/wp-content/plugins/ fluentform/vendor/wpfluent/framework/src/WPFluent/Database/Orm/Concerns/HasAttributes. php(453): FluentForm\Framework\Database\Orm\Model->getAttributeValue() #8 /home/ mrsclean/public_html/wp-content/plugins/fluentform/vendor/wpfluent/framework/ src/WPFluent/Database/Orm/Model.php(1989): FluentForm\Framework\Database\Orm\ Model->getAttribute() #9 /home/mrsclean/public_html/wp-content/plugins/fluentform/ app/Helpers/Helper.php(750): FluentForm\Framework\Database\Orm\Model->__get()# 10 /home/mrsclean/public_html/wp-content/plugins/fluentform/app/Modules/Widgets/ FluentFormWidget.php(104): FluentForm\App\Helpers\Helper::getForms() #11 /home/ mrsclean/public_html/wp-content/plugins/fluentform/app/Modules/Widgets/FluentFormWidget. php(69): FluentForm\App\Modules\Widgets\FluentFormWidget->register_general_controls()# 12 /home/mrsclean/public_html/wp-content/plugins/elementor/includes/base/controls- stack.php(2435): FluentForm\App\Modules\Widgets\FluentFormWidget->register_controls()# 13 /home/mrsclean/public_html/wp-content/plugins/elementor/includes/base/widget- base.php(1049): Elementor\Controls_Stack->init_controls() #14 /home/mrsclean/ public_html/wp-content/plugins/elementor/includes/base/controls-stack.php(570): Elementor\Widget_Base->init_controls() #15 /home/mrsclean/public_html/wp-content/ plugins/elementor/includes/base/widget-base.php(185): Elementor\Controls_Stack- >get_stack() #16 /home/mrsclean/public_html/wp-content/plugins/elementor/includes/ base/controls-stack.php(315): Elementor\Widget_Base->get_stack() #17 /home/mrsclean/ public_html/wp-content/plugins/elementor/includes/base/controls-stack.php(2524): Elementor\Controls_Stack->get_controls() #18 /home/mrsclean/public_html/wp-content/ plugins/elementor/includes/base/controls-stack.php(1161): Elementor\Controls_Stack- >sanitize_settings() #19 /home/mrsclean/public_html/wp-content/plugins/elementor/ includes/base/element-base.php(624): Elementor\Controls_Stack->get_data() #20/ home/mrsclean/public_html/wp-content/plugins/elementor/includes/base/widget-base. php(748): Elementor\Element_Base->get_raw_data() #21 /home/mrsclean/public_html/ wp-content/plugins/elementor/includes/base/element-base.php(629): Elementor\Widget_Base- >get_raw_data() #22 /home/mrsclean/public_html/wp-content/plugins/elementor/includes/ base/element-base.php(629): Elementor\Element_Base->get_raw_data() #23 /home/ mrsclean/public_html/wp-content/plugins/elementor/core/base/document.php(1105): Elementor\Element_Base->get_raw_data() #24 /home/mrsclean/public_html/wp-content/ plugins/elementor/core/base/document.php(738): Elementor\Core\Base\Document-> get_elements_raw_data() #25 /home/mrsclean/public_html/wp-content/plugins/elementor/ includes/base/controls-stack.php(1071): Elementor\Core\Base\Document->get_initial_config()# 26 /home/mrsclean/public_html/wp-content/plugins/elementor/core/editor/loader/ common/editor-common-scripts-settings.php(40): Elementor\Controls_Stack->get_config()# 27 /home/mrsclean/public_html/wp-content/plugins/elementor/core/editor/loader/ v2/editor-v2-loader.php(172): Elementor\Core\Editor\Loader\Common\Editor_Common_Scripts_Settings:: get() #28 /home/mrsclean/public_html/wp-content/plugins/elementor/core/editor/ editor.php(355): Elementor\Core\Editor\Loader\V2\Editor_V2_Loader->enqueue_scripts()# 29 /home/mrsclean/public_html/wp-includes/class-wp-hook.php(341): Elementor\Core\ Editor\Editor->enqueue_scripts() #30 /home/mrsclean/public_html/wp-includes/class- wp-hook.php(365): WP_Hook->apply_filters() #31 /home/mrsclean/public_html/wp- includes/plugin.php(522): WP_Hook->do_action() #32 /home/mrsclean/public_html/ wp-includes/script-loader.php(2311): do_action() #33 /home/mrsclean/public_html/ wp-includes/class-wp-hook.php(341): wp_enqueue_scripts() #34 /home/mrsclean/public_html/ wp-includes/class-wp-hook.php(365): WP_Hook->apply_filters() #35 /home/mrsclean/ public_html/wp-includes/plugin.php(522): WP_Hook->do_action() #36 /home/mrsclean/ public_html/wp-includes/general-template.php(3197): do_action() #37 /home/mrsclean/ public_html/wp-content/plugins/elementor/includes/editor-templates/editor-wrapper. php(35): wp_head() #38 /home/mrsclean/public_html/wp-content/plugins/elementor/ core/editor/loader/v2/editor-v2-loader.php(222): include(‘/home/mrsclean/…’) # 39 /home/mrsclean/public_html/wp-content/plugins/elementor/core/editor/editor. php(160): Elementor\Core\Editor\Loader\V2\Editor_V2_Loader->print_root_template()# 40 /home/mrsclean/public_html/wp-includes/class-wp-hook.php(341): Elementor\Core\ Editor\Editor->init() #41 /home/mrsclean/public_html/wp-includes/class-wp-hook. php(365): WP_Hook->apply_filters() #42 /home/mrsclean/public_html/wp-includes/ plugin.php(522): WP_Hook->do_action() #43 /home/mrsclean/public_html/wp-admin/ admin.php(424): do_action() #44 /home/mrsclean/public_html/wp-admin/post.php( 12): require_once(‘/home/mrsclean/…’) #45 {main} thrown in **/home/mrsclean/public_html/ wp-content/plugins/fluentform/vendor/wpfluent/framework/src/WPFluent/Support/ Str.php** on line **1318** * 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If you continue to have problems, please try the [support forums](https://wordpress.org/support/forums/). * [Learn more about troubleshooting WordPress.](https://wordpress.org/documentation/article/faq-troubleshooting/) * The page I need help with: _[[log in](https://login.wordpress.org/?redirect_to=https%3A%2F%2Fwordpress.org%2Fsupport%2Ftopic%2Ffluent-form-not-working%2F%3Foutput_format%3Dmd&locale=en_US) to see the link]_ Viewing 1 replies (of 1 total) * Moderator [threadi](https://wordpress.org/support/users/threadi/) * (@threadi) * [4 days, 14 hours ago](https://wordpress.org/support/topic/fluent-form-not-working/#post-18875511) * I would recommend that you contact the Fluent Forms support forum: [https://wordpress.org/support/plugin/fluentform/](https://wordpress.org/support/plugin/fluentform/) Viewing 1 replies (of 1 total) You must be [logged in](https://login.wordpress.org/?redirect_to=https%3A%2F%2Fwordpress.org%2Fsupport%2Ftopic%2Ffluent-form-not-working%2F%3Foutput_format%3Dmd&locale=en_US) to reply to this topic. * In: [Fixing WordPress](https://wordpress.org/support/forum/how-to-and-troubleshooting/) * 1 reply * 2 participants * Last reply from: [threadi](https://wordpress.org/support/users/threadi/) * Last activity: [4 days, 14 hours ago](https://wordpress.org/support/topic/fluent-form-not-working/#post-18875511) * Status: not resolved ## Topics ### Topics with no replies ### Non-support topics ### Resolved topics ### Unresolved topics ### All topics