Getting unkown 500 error always in Pages+Access

Hello. I use Cloudflare Access to restrict to view preview deployment of Cloudflare Pages, from Pages config “Access policy” → “Enable Access Policy”.

But recently (about two months ago), my preview deployments via auth by Access (any auth method, too) return unknown 500 errors always.

The login attempt was successful and I am allowed access on Access.

sc

I changed email address of my Cloudflare account just before the problems happened, it causes this accident ?