Dunooon-
That was the same problem I had with mine, they would lock and unlock randomly too.
Folding is not to bad just push up the red bit and push forward as would any other umbrella fold but make sure the clip at the side is out, it can jam or snap off it will also prob unclip very easily! Check the backrest mine went lop sided when reclined. Ended up ina skip but I have a friend who loves hers.
It was Fi's BJCM I bought she said she was getting a double!