There's a file online somewhere telling you how to adjust the lens helical, I did save it I'll try and find it & email it. There's two small screws inside the helical mount that need adjusting.
The camera's actually made by Gaoersi so the lens helical is the same. When I bought mine the helicals were set specifically for the two lenses before shipping. It's a bit fiddly that's why the chines seller wanted to know exactly what lenses, there was a difference between my 90mm SA & Grandagon, so I had to chose which to use,
File's already sent