I can't get the back cover of my watch back on?

Question

it's a lorus sports watch and it was tight to get off but i did and replaced the battery. the problem is that when i try to put the back cover on again it won't go on, i've forced it quite hard but it wont pop back on. i found a small slit in the back of the cover but i can't find anything on the watch that would correspond with.

i had it on for a night but when i woke up and took my watch off if came off again

any help greatly appreciated

Answer 1

get a thick cloth and cover the back of the watch with it. then get a small rubber hammer and tap it lightly. make sure that the face of the watch is protected. if that doesn't work take it to a jeweler