This week we are staying at CC club site at Braithwaite village in Cumbria and as it is such a nice day decided to take down our Issabella sun shade.
To do we closed the caravan door and did the said deed, on trying to open the door it had locked it's self with the key inside.
I think the same thing had happened to Eribamotters?.
After a lot of messing about with plastic strapping tape we managed to open the kitchen window and reach through and release the door catch. Tried to do it again and not able to get it to lock. Busy now trying to get a spare blank.
The next delays will be were to hide it.

Warden on site reckons that he never locks is cassette toilet door gas has a spare key hidden inside. where would you hide yours?

I have a magnetic key box affixed to the chassis.