ride height??????

[vw754]

The story go's like this, rear coil spring broke on my car,i replaced only that spring with one from another A4 ,and noticed car was sitting 1 inch higher that side.(oh dear,should of replaced both) anyway i left it like this for around 6 months (passenger side rear 1 inch higher than rest of car)
After 6 months i decided to change all the springs in the car and replaced with 40mm koni springs. I also got 2 front shockers fitted from a 54 plate tdi s-line. (leaving the rears standard)

Now after the replacement koni's the passenger side rear still sits half to 1 inch higher
I noticed the car wasn't sitting rite and took it back to the garage,they took back springs out and re-fitted them. cars still the same drivers side rear is ok,passenger side still higher.......you guys tell me what it could be?

Ive been told alot of different things......rear shocker maybe binding, keeping that side lifted, ive checked koni spring part numbers and made sure springs are sitting in the cups as they should.

any help please!