我在函数内的第一个返回值没有返回任何内容

So I have a function which controls the turn taking of a player, and I want it to return FAILURE when the player unsuccessfully takes a turn. (The game is connect 4). I obviously want it to return success when the turn is valid, however.... Even when I return SUCCESS it's requiring two return SUCCESS to return a single success. Here is the code:So I have a function which controls the turn ta