Electronic Key Safe

[cts1975]

I have one these https://www.securikey.co.uk/product/electronic-key... fitted in one of my units. The mechanism is battery operated with 4 AA batteries. The mechanism has started to slow down and doesn't sound very convincing! I have changed the batteries for a set of brand new Duracell's but it still sounds slow/lazy when operating.
Does anybody have any experience with these ? Are they able to be repaired?
I could buy another but this one is seriously fixed/bonded to the wall so I would prefer to fix this one if possible.
Thanks