Cannot open the driver door when unlocking from the outside.

[Rahxephon]

There's a problem w/ my Vitz. This morning I unlocked the door using the remote. However, the driver door wouldn't open. I got inside my car using one of the back doors. The driver door lock was in an unlocked position; I could see the orange mark on it. I was able to open the driver door from the inside.

I thought the problem was temporary. However, it happened again after I got off work this evening. I still couldn't open the driver door (from the outside), even when the orange unlock mark is shown (inside).

I can still open the driver door from the outside, if the door is unlocked and then opened from the inside FIRST - then closed without (re)locking it. If the door is unlocked from the outside, without opening from the inside first, it won't open - even when the door orange unlock mark is visible. I hope this is not too confusing.

Any suggestions? Can I fix this myself? Will this be covered under a warranty? Thanks in advance.