WordPress Elementor Pro Issue

Hello,

We use Elementor Pro to develop and manage our website. the problem is we are now unable to save pages when using the elementor editor.

We get the "internal server error 504"

We have done the following with no luck:
* increased the allowed memory limit to 2048M
* increased the set_time_limit(180)
* <IfModule mod_substitute.c>
SubstituteMaxLineLength 10M
</IfModule>

We need a WordPress expert that knows Elementor and has system admin skills.

Thanks!