NB2.5 Is my Door Lock Actuator broken?

I seem to have an intermittent fault on the drivers side door lock whereby the door always unlocks fine, however, when you go to close the door it doesn’t close and just banks against the striker.

Upon further inspection the dark part of the lock seems to still be in the way.

Working (mocked up from pic of the passenger side)

Broken side (mocked up from passenger side plus my excellent paint skills! LOL Annoying I forgot to take a photo before fixing it)

The only way I could get it to close was to use a flat bladed screwdriver and pressure it back down. I’ve applied some wd40 to lubricate it but I imagine its broken.

Just before I spend about £150 on a replacement is there anything else that might be causing it?

NB Makes no difference whether you use a key or remote.

I’ve actually gone ahead and ordered a new lock from MX-5Parts so I’ll see if that fixes it.