Hi,
thanks for your post, and sorry for the trouble.
I’m really sorry to hear about this, but I will gladly work with you to fix this as soon as possible!
At first, I’ll need some more information though: What menus are you talking about? Regular WordPress navigation menus? Do you get any error messages? Have you tried with WP_DEBUG set to true?
And while the PHP max_value should be fine, could this be a PHP Memory Limit issue? To fix that, please try increasing that PHP memory limit on the server, by increasing the value of the WP_MEMORY_LIMIT constant in the wp-config.php file, e.g. to 512M, via the instructions from https://codex.ww.wp.xz.cn/Editing_wp-config.php#Increasing_memory_allocated_to_PHP
Regards,
Tobias