EOS M lens release pin stuck in

I have a Canon EOS M with EF-M 22mm lens only.

Lately, I've experienced that the lens release pin is stuck in. The lens appears to fit to the body firmly but the pin doesn't click into place. It remains flush with the surface of the body's lens mount.

While the lens remains in place I'm not too worried but I am a little concerned that one day the lens might work its way loose and just fall off. I tend to carry the camera with me on the bike so it may be prone to some vibrations.

Apart from sending it away for repair, any suggestions?

I'd be inclined to use a paperclip to very carefully press the pin in just a little, to see if the pin itself is just stuck - there's a good chance that if it has got dust or dirt on it, you could clear the problem.
If the pin goes in a little bit but doesn't spring back the spring itself could be stuck or broken, in which case you have to get it looked at.