Door lock won't lock

Well OT here but here goes.... New house has this type of door lock. To lock from the inside you lift the handle, let it return to its normal position and then turn the snib towards the door. One of these isn't working. The handle only lifts part way - not enough to allow the snib (or the key from the outside) to turn.

Shortly before it stopped working I heard a door slam. Not sure which one it was but it may have been this one and shaken something up inside.

Does anyone know, bearing in mind it's a public holiday heading into the weekend, if there's a way to 're-set' the locking mechanism? TIA.

Attached files

Does the handle lift all the way when the door is open? If so, it is likely to be an issue with the hinges rather than the lock.

Do you have any powdered graphite you can puff into the mechanism in case it it just stiff? If not, a 6B or 8B pencil rubbed on a file or sandpaper will generate some.
This often frees up mechanisms that are stiff whether a little corroded or dirty, and won't do any harm, unlike oil, which gathers dirt and bungs up the mechanism.
Like Kai suggests, checking the alignment with the strike plate when in the closed position is worth doing.

I think we have a similar lock on our garage door - it has pins that come out the top and bottom of the door into the framing. With ours you have to lock the door before lifting the handle.
Perhaps one of the pins is out of alignment? I think ours has plastic blocks in the top and bottom of the door that the pins go thru.