no new emails

Have received no new emaiils since afternoon of 4/21/20. [ The emails are also forwarded to Thunderbird] Saw message at bottom of Comcast email screen on 4/22/20 asking did I log in yesterday on Chrome from Nigeria. Answer was obviously no. Comcast then will, and has ,sent me a reset code number, but once I get it and go to Comcast page, or their email page, can find no place to enter the code.  Tried another way to verify who I am, but once completed, same thing. Get reset code but don't know what to do with it. Please help an old man solve this.