Hello,
I have news, after intensive research I came to the conclusion.
Apparently it was AI crawlers.
I made a custom plugin “activity log” to see every movement on the page in real time, and I noticed that mainly Facebook was sending its AI crawlers to my website to view products, so I set a rule on cloudflare that if they go to view products where filters like “color, product type….” are enabled, so that it blocks them, because when 5 such requests came at once, it overloaded the RAM terribly, so I am still indexable for AI and normally for browsers, but they only view products, and not the filters in the product archive. I think that was the problem there, at least so far I haven’t gotten any errors, that’s probably why the error occurred once but not the next time.
I think we can close this, if something happens I’ll write another topic, anyway thanks for the help 😉