Yeah, that mudguard wheel is a total POS as far as I'm concerned. It basically means the bike can ONLY be rolled in the backwards direction, ie that direction where the little 3rd wheel ends up in the back. Then it works. When trying to push with that little wheel at the front, the action naturally puts more weight on that little wheel which makes it bind, which puts even more weight on it, which makes it bind more, which... you can see where that is going, nowhere.

I have tried improving the wheel but the only good solution is to throw it away and use a 3rd party easy rolling bearing-mounted wheel. The ones from bike gang work, unfortunately they are made from HARD plastic so hardly a nicely rolling softish wheel.