You just have a key locking back door type installation. One that will not lock you out when you go out to hang out the washing. When I surveyed for DG companies I used to have to specify what the customer wanted, usually key locking for the back door and pull handle lever latch for the front entry exit door.
I take it you have multilocking set up. We would have to change the locking system if it were ever wrong, not just the handles, but I have been out of the DG business for about 15 years so things may have changed. Have a look and see if you can identify lock make and google them for contact details. But others on here may help.
Bickyz i am interested in if you can change the lock configuration too.
I think mine works the same as your front door when unlocked can be open from inside or outside by pulling the handle down.
But other doors when unlocked will only allow the inside handle to be pulled down and the outside handle wont operate, to get in from outside the key must be used.
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