Wheel of Fortune Not accepting my letters.

Has anyone else had this problem? I just finished playing a bonus round game, (in a tournament game). I got the solution correct but it said i was wrong, then the bot said the same thing i said and got it.  The other day I did a bonus round and one letter i selected was D and it said there was no D. The solution was "ducks and ducklings". !!! I am starting to not like this game anymore.