Hi everyone, does anyone know how to fix or service these please?

I’ve just returned from my local jeweller thinking that it needed a new battery but it wasn’t a battery problem, the watch had just stopped working. The jeweller thought that due to it being stored for a while, that it might have been caused by the battery leaking and it might result in a costly repair. As it’s an old watch and not worth much it’s probably not cost effective to repair, however, I rather like it and would like it saved if possible. I’ve attached a pic of the offending item.



Kind regards.
Pete.