After having many micro 520 error issues, I’ve talked to my server provider, IONOS, and they confirmed that the server is working properly.
To have a confirmation, they asked me to pause Cloudflare, return the original IONOS DNS addresses, and check if the site is running fine.
That’s what I’ve done, and now everything looks ok.
Is Cloudflare having any issue?
What can be the cause of this problem, since IONOS says that everything is alright on their side?
Thank you very much for your answer.