[moltuae]

It's a long time since I tried reprogramming remote key fobs myself but, according to my notes, these are the correct procedures that worked. I do remember it's a bit of a faff, and it can take several attempts to get it right, especially if you have 2 or more fobs to program.

(Note the additional step required to program multiple remote fobs)

Key Fob Programming
VW/ Audi/ Seat/ Skoda

Remote Control Programming (1997 ON)
Procedure
1. Switch Ignition ON and leave 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 exactly the same, except you press the unlock button 2, 3 or 4 times for 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 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 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 tuned in..