Certain users have no Facebook account, either deactivated or on behalf of others, and want to complain to Facebook without an account for any malfunction call 650-543-4800 or, +1-855-974-1385(for quick support) if the unauthorized activity has been found, etc. So, in this case, the following details or a discussion will indeed guide you to complain to Facebook. Please consider it and jot down the essential points:

https://groups.google.com/a/chromium.org/g/chromium-reviews/c/eLp1Dq2aMzw