not accepting under guarantee

So I bought an AG mobile chrome plus at an edgars store in hartswater on 21/12/14 now I am in orkney and there is only a jet around so I figured that whilst jet is part of edgars I would have no problem returning the phone there I got there stricly saying that it cannot be done so I contacted the store of purchase and the guy said its impossible it must be done today I returned to jet only them to say that they can help me on monday only when custemor care is online 1. Custermor care should be a 24 hour service that is open to the customers the one who pay sallaries 2. Why can I buy with my edgars gift card at jet stores shouldent they be able to return goods also then