I, too am a new owner of the SQ-Am. When I received it, I discovered the Lens Release Button (in front of the Shutter Speed Dial) required a little more persuasion than should be normal to press it down and thus release the lens lock. After a little persuasion, (thumbnail), the lens was removed, and I exercised the button repeatedly, and was able to see the links inside the body. I carefully and sparingly lubricated the sliding and linkage parts, and the button became easier to activate when removing a lens.
Also, there is a tiny amount of "wiggle room" when turning the mounted lens collar back and forth. Wiggling the lens in a counter-clockwise direction (when looking at the lens from the front), seems to relieve the imagined stress on the Lens Release Button.
I hope your problem is as simple as this. Let us know the result. ...and we hope you solve the problem soon.