Question about Zhiyun Smooth 4 Smartphone Gimbal

I bought the gimbal here new. It says it is compatible with iPhone 12 Pro Max. Even after following the instructions EXACTLY, I can neither balance the device cleanly nor connect it to the iPhone 12 pro Max. Before I pack the device nicely and return it with O stars: Does anyone have a tip on how I can get this thing to work? Unfortunately, the support centre in Frankfurt is unusable.