I have an error which is as follows:
The REST API is one way WordPress and other applications communicate with the server. An example is the Block Editor screen, which relies on this to display and save your posts and pages.
The REST API request failed due to an error.
Error: cURL error 35: Peer reports it experienced an internal error. (http_request_failed)
Are you using Flexible mode from Cloudfare? If yes, remove your domain from Cloudfare and make your own free SSL Certificate from ZeroSSL. Cause it will only be fixed if you use the Full mode, you know.
I am also facing that problem, but the problem had gone/fixed after I used ZeroSSL and install it on Infinityfree CPanel. You could just use or Generate your Certificate using the Infinityfree generate tool.