Why do i have the option to aend a message again?

There was a fake profile that i send a message and then immediately blocked it.its user had a 1 message limit until they accept the chat,so i could only send 1 message until they accepted it.so after some months i unblocked the profile and when i checked out of curiosity i could again send 1 message,even if i had already send 1 before.so what happened .the 1 message limit was still there but i had the option to send again 1 message even though i used it in the past