It can be a bit tricky to do sometimes had some issues myself! do you have vcds or vcds lite at your disposal if so I will include the following link to assist
https://www.ross-tech.com/vag-com/cars/vw-remote-matching.html if not
Remote Control Programming (1997 ON)
Procedure
1. Switch Ignition ON and leave the key in the ignition.
2. Mechanically lock the vehicle using the Drivers door using a second
key.
3. Using the remote control press the Unlock button once, and the horn
will sound once.
4. Wait 6 seconds and press the unlock button once to activate the coding
procedure. The remote control will now be programmed.
NOTE: When performing programming on additional remotes the procedure
is the same, except you press the unlock button 2, 3 or 4 times for the
different remote.
For example: If programming 2 remotes press the unlock button twice with
a 1-second interval between each press, repeat for 3 and 4 remotes.
5. Switch Ignition OFF.
6. Remove key from the ignition and check for operation.
7. The coding procedure can be repeated up to 4 times for additional remotes.
8. The ignition must be switched OFF between programming each remote
control.
Remote Control Erasing (1997 ON)
Procedure
1. Switch Ignition ON and leave the key in the ignition.
2. Mechanically lock the vehicle using the Drivers door using a second
key.
3. Press the remote control unlock button 5 times in 1 second intervals.
A short horn will sound.
4. Wait 6 seconds and press the unlock button once to activate memory
erase.
5. Switch ignition OFF, all remotes are now erased.
