Cant Activate Plugin After WorPress Update

Hi There

When I try to activate the courier guy plugin I get the following error both on the front end & within the WordPress admin panel

” Warning: session_start(): open(undefined/sess_1vnl3pc9p523k1ms96nnqphtfp, O_RDWR) failed: No such file or directory (2) in /home/xanadtrr/public_html/wp-content/plugins/the-courier-guy/Core/TCG_Plugin.php on line 25

Warning: session_start(): Failed to read session data: files (path: undefined) in /home/xanadtrr/public_html/wp-content/plugins/the-courier-guy/Core/TCG_Plugin.php on line 25

Warning: Cannot modify header information – headers already sent by (output started at /home/xanadtrr/public_html/wp-content/plugins/the-courier-guy/Core/TCG_Plugin.php:25) in /home/xanadtrr/public_html/wp-content/plugins/wp-super-cache/wp-cache-phase2.php on line 1338″

When I deactivate the plugin the error messages disappears but this is the only courier company we are currently using so it has to work any help will be highly appreciated I have tried the following already

Install / re-install the plugin via FTP / via WordPress panel
Install Super catch plugin / re-install
Checking if the file path is correct and it looks correct to me

the current WordPress version is WordPress 5.3.2 and its the Divi theme Version: 4.2.2

Hope there I someone that can assist

Kind Regards

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