Title: PHP Fatal error: Uncaught ValueError: Unknown format specifier &#8220;a&#8221;
Last modified: January 2, 2024

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# PHP Fatal error: Uncaught ValueError: Unknown format specifier “a”

 *  Resolved [Borja Abad](https://wordpress.org/support/users/soportecibeles/)
 * (@soportecibeles)
 * [2 years, 5 months ago](https://wordpress.org/support/topic/php-fatal-error-uncaught-valueerror-unknown-format-specifier-a/)
 * I have the following error after upgrading from php 7.4 to 8.2
 * PHP Fatal error: Uncaught ValueError: Unknown format specifier “a” in /wp-content/
   plugins/flexible-checkout-fields/src/Tracker/DeactivationTracker.php:52

Viewing 7 replies - 1 through 7 (of 7 total)

 *  Plugin Support [rzepsen](https://wordpress.org/support/users/rzepsen/)
 * (@rzepsen)
 * [2 years, 5 months ago](https://wordpress.org/support/topic/php-fatal-error-uncaught-valueerror-unknown-format-specifier-a/#post-17314468)
 * Hello Borja,
 * Thank you for trying the plugin. It looks like the problem may originate in the
   translation of the phrase, _Contact us on %1$sthe support forum%2$s or read %
   3$sthe plugin FAQ%4$s for help._
 * I checked the translation of this phrase for several languages [https://translate.wordpress.org/projects/wp-plugins/flexible-checkout-fields/stable/](https://translate.wordpress.org/projects/wp-plugins/flexible-checkout-fields/stable/),
   and it seems to be ok.
 * Could you tell me do you translate your site and therefore the plugin into any
   language? If so, please tell me which one, and I will verify the correctness 
   of the translation in WordPress.org.
 * If you translate our plugin using another plugin, please check if the strings%
   1$s, %2$s, %3$s, %4$s are included in the translation.
 * If they are not there, you will need to add them as they appear in the source
   phrase.
 *  Thread Starter [Borja Abad](https://wordpress.org/support/users/soportecibeles/)
 * (@soportecibeles)
 * [2 years, 5 months ago](https://wordpress.org/support/topic/php-fatal-error-uncaught-valueerror-unknown-format-specifier-a/#post-17316934)
 * Hello, thank you for your quick response.
 * Indeed we are using a very popular translation plugin such as WPML.
 * ![](https://i0.wp.com/triallibreria.eu/wp-content/uploads/2024/01/Captura-de-
   pantalla-2024-01-04-080004.jpg?ssl=1)
 * The translation strings seem fine. Likewise, if I put a return false in the function,
   my code no longer fails. You can also try containing the function with a try-
   catch.
 * I am very grateful to you in advance.
    -  This reply was modified 2 years, 5 months ago by [Borja Abad](https://wordpress.org/support/users/soportecibeles/).
 *  Plugin Support [rzepsen](https://wordpress.org/support/users/rzepsen/)
 * (@rzepsen)
 * [2 years, 5 months ago](https://wordpress.org/support/topic/php-fatal-error-uncaught-valueerror-unknown-format-specifier-a/#post-17319670)
 * Hi Borja,
 * Many thanks for that screen showing that translation to Spanish is not as it 
   should be.
 * Could you take a look at %1$s and %3$s.? In the translation, you used %1$el, 
   which should be %1$s.
 * The same is with %3$las it should be %3$s.
 * This last letter “s” is also part of the placeholder. Please, make this changes
   and run a test.
 *  Thread Starter [Borja Abad](https://wordpress.org/support/users/soportecibeles/)
 * (@soportecibeles)
 * [2 years, 5 months ago](https://wordpress.org/support/topic/php-fatal-error-uncaught-valueerror-unknown-format-specifier-a/#post-17319864)
 * Hello rzepsen, thanks for your help, we have solved the problem.
 * The strange thing here is that we have never translated those strings manually
   or touched that configuration, which comes by default. We have also not had this
   problem before with WPML and use it on other websites.
 * There seem to be many threads from many plugins with the same problems when updating
   to php8.
 * [https://wpml.org/errata/php-8-php-fatal-error-uncaught-valueerror-unknown-format-specifier-in/](https://wpml.org/errata/php-8-php-fatal-error-uncaught-valueerror-unknown-format-specifier-in/)
 * [https://wordpress.org/support/topic/under-php-8-0-uncaught-valueerror-unknown-format-specifier-s-solved/](https://wordpress.org/support/topic/under-php-8-0-uncaught-valueerror-unknown-format-specifier-s-solved/)
 * I guess containing that possible error will help other users.
 * Receives a warm greeting.
 *  Plugin Support [rzepsen](https://wordpress.org/support/users/rzepsen/)
 * (@rzepsen)
 * [2 years, 5 months ago](https://wordpress.org/support/topic/php-fatal-error-uncaught-valueerror-unknown-format-specifier-a/#post-17325440)
 * Hi Borja,
 * It’s great to hear that problem was solved. It is difficult to determine what,
   if anything, actually replaced placeholders in the translations.
 * Changing the PHP version to 8 displayed this error. I suspect that this problem
   previously occurred, only PHP version 7.4 did not display it.
 * Is there anything else I can help you with?
 *  Thread Starter [Borja Abad](https://wordpress.org/support/users/soportecibeles/)
 * (@soportecibeles)
 * [2 years, 5 months ago](https://wordpress.org/support/topic/php-fatal-error-uncaught-valueerror-unknown-format-specifier-a/#post-17325443)
 * Thaks for all!
 *  Plugin Support [rzepsen](https://wordpress.org/support/users/rzepsen/)
 * (@rzepsen)
 * [2 years, 5 months ago](https://wordpress.org/support/topic/php-fatal-error-uncaught-valueerror-unknown-format-specifier-a/#post-17328329)
 * Ok Borja
 * I mark this thread as resolved.

Viewing 7 replies - 1 through 7 (of 7 total)

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## Tags

 * [fatal error](https://wordpress.org/support/topic-tag/fatal-error/)
 * [update.php](https://wordpress.org/support/topic-tag/update-php/)

 * 10 replies
 * 2 participants
 * Last reply from: [rzepsen](https://wordpress.org/support/users/rzepsen/)
 * Last activity: [2 years, 5 months ago](https://wordpress.org/support/topic/php-fatal-error-uncaught-valueerror-unknown-format-specifier-a/#post-17328329)
 * Status: resolved