PHP and PHP-FPM

PHP
,
1

Hello,
The Front-end of a website is React and the Back-End is Laravel. The developer uses PHP on his system and Laravel runs on port 8000. I set up this website on a server using PHP-FPM running Laravel on port 9000. Sometimes the following error is displayed when opening pages:

Unit
Unit1053×651 32.4 KB

I use Docker. Could this error be caused by PHP-FPM?

Thank you.