Well it isnt a matter of reprogramming the unit to the remotes. The remotes shoulf set a different code each time.
The problem is that the main control unit is not changeing the code it is set to because it cant. It is set to a preset frequency.
Unfortunately with the older units the manufacturer set multiple units to one code and made sure that they didnt ship the units with that code to the same area.
Problem is when the new rolling code came out there were a lot of old openers that would respond to the signal because it was on the same freq that it was.
The actual frequency that your unit opoerates on can not be changed. The codes that are transmitted are not actually codes but radio frequencys.
When the remotes are programmed they scan for the frequency that is being used. IUf that frequency is being used by anotherr unit then the only option is to get a unit that does not use that frequerncy.
This is the case here. It isnt a matter of code learning or unlearning. The frequency that your unit operates on is that and only that. If you look on th emain board you will see a tall oval tin component with writing on th weside that has something like 103.22MHZ.
That is the frequncy that your unit operates on. Change that component to one like it with a different frequency and your problem is solved.
All the newer units have rolling codes that they use to eliminate this problem.