So I accidentally took my website offline for 30min while trying to fix this.
I’ve decided to hand it over to someone with actual wordpress knowledge (which is not me, but thank you so much for your help!)
Nope, got a 500error when I tried that.
I checked the permission, it is 755
And I went to the wp-content folder, I added the code bit this did not work.
The current code is:
define(‘WP_TEMP_DIR’, ‘/var/www/vhosts/intoflow.be/httpdocs/wp-content/uploads’);
I don’t know if that has anything to do with it?