You have been sold older model springs but you have a post 95 vehical with the smaller spring caps. the pig tails on the spring are slightly bigger on the MK2/MK3 pre 95.
I have the same problem and i reset it a few times, its been fine for about 6 months now which is a supprise but there are three options
Caps from the dealer are £15.00 each (need to get the for a MK2) or they insist on giving you the smaller ones
Scap yard, couple quid each.
Or you can fit lowering caps which are again... arround £15.00 each and lower the car another 10/15mm