Same happened to me a week ago with my gd.
Person in back.
Pulled inside lever, not working.
I pulled outside handle, not working.
Went shopping and all working when returned.
Only explanation was it had neen really cold overnight so only assume frozen inside door.
Yours seems it is a faulty mechanism.
My son's fd had similar but his would open randomly.
It was due mot for which not being able to open door is a failure.
Not sure what was done but said garage sprayed into door area, how or with what not known, but since then he has had no further problem.