I had a similar problem.

Removed door panel which includes removing the inner door handle etc etc.

When I reassembled everything seemed fine except the door would not correctly lock or unlock.

I thought the lock button was mis-aligned.

I ended up taking it apart all again to reassemble and find the same problem.

I eventually found by accident that when you reconnect the cable to the inner door handle there is the opportunity to clip the wire sheath in wrongly creating too much pre tension in the cable. I was clipping it in too far back in the holder.

It was a EUREKA moment for sure!!

This may be your problem as it is not obvious you have done anything wrong.

89 300CE
149k kms