Welcome to RWG Do you have a link to the Trusted Dealer you got this rep from please? Seems an odd movement choice, plus a photo of the movement will help clear things up, and assist helping you further.
It sounds like you may have a Z2, this is also known as the POS Clone, it looks like an ETA, but its actually a clone of the Clone ETA, and some parts are incompatible with one another, plus there are common issues with the Z2 movement, and these are what you address here. Failing that, talking of the date changing that way, you may even have a DG movement in there of sorts.