When I push in the program little hole, a red...

Question

when i push in the program hole, a red light used to come on ,then I could put in the three digit number, now nothing at all happens. I changed the batteries in the remote. still nothing. Did I push to hard and break something? the set is a 13 inch Magnavox PR1357 B121 If this remote is not good anymore can you tell me where to get a new one for this model. thank you Elvira.