I say, I say, I say .... did you hear the one about ....
Just having a dig at the fact you posted the same request 3 times !!
According to the website, Citroën UK are located in Slough and Customer Services is 0870 6069099
Citroën Information: - Authorised Repairers, Services and Accessories - 0800 262 262
Citroën Assist - 0800 0565099
Citroën Fleet - 01628 663045 (also 0845 7940940)
0870 6069000 is also Cust. Services at Head office, Slough which is at odds with the fax number code (01753) you gave which is for IVER in Bucks where Citroën don't even have a branch ???