Hi there and welcome
If you remove the battery and then try to slide it over, does it then slide over?
ok, when you close it your making sure to slide it to the very right first so it is extended as far as possible, then push down and slide it to the left to clip in?
What happens when you do this?
Ok, I want to make sure your using the right compartment for this, look at the section 1 Setting up your Camera here
The battery needs to be pushed down till it clips in then you slide the cover over.
You have tried now with the battery out as well? Just to rule out the battery as the issue.
How do you mean it will not move? It will not open at all? Its jammed in one position?
Or it will close but will not stay locked?
I showed you the document I am looking at which is for the M550 which is the model you indicated you had.
Use a bit of force as you cannot bend it when the battery is in, and push against it (use a paperclip) to try to get it to snap back and cover over the battery.
Let me know the results.
ok.. let me know when you did my last instructions please
I never said it shows the orange lock so not really sure what you mean with that....
But ok, you need to go here for your refund
ok, but as you have requested a refund, we cannot continue any further.
Thanks and all the best.