How to fix this Fatal error?

[JxstErg1]

Hi and welcome to the forum! Can you try this?

Unabel to upload autoload_static.php from my local composer folder to server

There is a limit of 1 MB for PHP files on our hosting, so any file larger than that would be automatically deleted. One possible way I see is to regenerate your Composer files without the --optimize-autoloader option. This may give you a small performance hit in production, but it avoids these large generated PHP files with class information.

Maybe the autoload_static.php file your software is using is optimized, that’s why it gets deleted after your website is uploaded because it weighs more than free hosting allows (1 MB).