Problems transferring updates back to live server For quite a long time i've updated and amended Craft by taking a copy of the files and database (.zip) from the live server, making the updates/changes/amendments locally and then transferring everything back (.zip).

Just recently i've had a couple of instances where i've made amendments and updates to an older site (Craft 3.1x to 3.4x) and everything has been fine locally. I then deploy the updated version back to the live environment and immediately get the error Craft can’t connect to the database with the credentials in craft/config/db.php.

I know this is a familiar error for some but i've only recently started seeing it.  I've spent a long time looking for and trying fixes but nothing seems to work for me!?

Mac OS Catalina
MAMP Pro 5.7
PHP 7.2.22
MySQL 5.7.26

Like I say, this is actually quite a new problem for me and I don't know what has changed?  Any help is very much appreciated.
From Craft Support:
Assuming the credentials in your .env are correct on that site, could you run ./craft clear-caches/all (or manually empty your web/cpresources and storage/runtime