I started potty training my 3 year old son about 3 weeks ago. He has been doing great but will only go to the potty when bottomless. Whenever I’ve tried putting shorts on him (with no underwear) he has an accident. When he is wearing shorts I will repeatedly ask him through out the day if he has to go to the potty. He will tell me no and then has an accident a few minutes later. Any tips on how to get past this?