I was just starting playing this game and ths just pop up when i first playing on my phone... 
Right as you started playing (A line or 2 into the dialog?)
(If so, it might be an issue with the outline shader I'm using-- I'll try and follow up with the creator of the shader to see what's wrong, as this doesn't occur on the devices I used to test :0)
The desktop versions shouldn't have these issues in the meantime if that's an option for you! Apologies for the inconvenience!