Autocenter fails

If i use the autocenter it is failing during the attempts with more or less the same amount in the same direction (DEC 40px; Atik 460; dynostar; LXP poth hub)
The problem startet after changing the scope
In the past i used 385mm focal length without problems. After changeing to a scope with 1600mm the problem started. Where i have to look for?
The platesolving seems to work

Regards
Karl