I got a message from a friend, don't know if this is true

This is fake, there is no such thing as a pending ban. Some extensions add those warnings to profiles with a CAUTION tag on Steamrep, but you do not have one of these. Additionally, "Waiting Approval" is not a valid type of tag/status/reputation, this has been edited in via the scammer to trick you.

Also, I split this post into its own thread.

Just as a follow up - your "friend" if you've known them for a while is likely compromised or even if they just added you could have been hijacked. Be sure to report the account to Valve so they can take the needed actions.