I own a jenday conure and when he get his wing clips he gets sweet beak ,sweet beak is a term I made up but it means that your bird will be like don't do that to me again but once he forgets about his wings being clipped he/ she should be fine.

Conures are very stubborn and dominate birds. Sometimes they need to be forced to do things they don't want to, stepping up being exactly that. Try taking him out and perching him on your hand/finger and take a perch or your other hand and press it above his feet on his belly until he is forced to step up. Do this is many times as needed until it is known he is going to have to step up.

Could he be in pain from the procedure, he doesn't sound to be himself, perhaps take him to the vet to be checked.

Has he had wings clipped before - was it done correctly?

i have had my jenday conure for 5 years and ever since i took him to get his wings clipped he is not stepping up this has gone on for about 4 weeks now and I thought it was that he doesn't trust me so i tried teaching him tricks like wave and nod he learned them but still doesn't step up i even tried a perch and he just bites it please help