Where can I fix my vacuum cleaner?

Batteries left discharged for a long time will deteriorate.

you may get some response if you take it back and say, simply and without elaboration "It doesn't work properly. It won't hold any charge"

XXX
February 2016

It's a Morphy Richards 2 in 1 machine... Argos have it for £80

If you have any warranty left on it then take it up with the vendor who sold it to you - clearly the battery is defective - a repair is very unlikely.

Given that you so seldom use it you might consider not bothering. The motor is a puny 100 Watts.

Good Luck...
February 2016