Can't send messages to my friend cause he changed his name [Client]

So, my friend "Blagoslovit" changed his name into "TheHolyOne", in my friend list his name still appears as "Blagoslovit", but in loby i see him as "TheHolyOne". The problem appears when he sends me a message and i am in game, i can t answer him with the "/r" comand nor with the "/msg playername" comand.