4 year old/almost 5 and not potty trained!

knottie235cbb4a3846f8b3

I have been having so much trouble with my son and potty training him. I made a prize bucket, bride him with buying him things, bought him a bunch of different varieties of potties or potty seats. The last few days I have hid the pullups and just keep putting underwear on him. He stays dry for a while but then when he pees he doesn't tell me. He has only shown interest a few times and has actually peed in the potty. I'm at such a loss!