My friend has used the EasyDCC system for over 20 years on his layout and I have to admit that programming on the programming track is not one of its strong or reliable points. I used to bring my NCE PowerCab portable DCC system for more reliably reading and writing CVs on its programming track, and he eventually bought the ESU LokProgrammer to reliable program the ESU decoders (and to be able to modify the sound projects, as he really likes the ESU decoders).
One big obstacle is that on EasyDCC you can't even reliably read (using the macro) CV values from many decoders, so you don't know if the change you made took or didn't take. At least that is what he sees on his system.
If you have a friend, model club, or a hobby shop close by using another brand DCC system, see if they can help you out in getting the loco to work again.