I would not advise this. 1) Cloudflare generally remembers your site settings after a delete/add cycle, and 2) It’s better to figure out exactly why this is happening so it doesn’t happen again.
If there’s nothing in Cloudflare logs, then there should be something in your server log. A 403 event has to show up somewhere.
I have server admin to add CloudFlare IPs to whitelist and there’s still no result.
So I decide to turn off CloudFlare Proxied (grey cloud) temporarily