Indeed there is something very wrong.

First this post is written in Aero section which is not intended for Helicopters. But we will move it to a correct section later.

This problem is usually caused by a wrong mounting of the GeoLink module or by mechanical setup of the model.

The best to try first is to engage Coaxial mode only and observe how well you can control the model. If it is drifting in a similar way, then the problem is rather in the helicopter configuration - especially Subtrims/swashplate levelling.

If you are using Coaxial mode to fly and then after flying engage the Position hold then there could be a problem.
I recommend to try Position Hold without prior usage of Coaxial mode to make sure it has no effect.

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Spirit System developer

Can you take a photo of how the module is mounted?
And how you are measuring the angle?

Very important thing is that Goblin and similar helicopters have tail boom not parallel with the rotor blades. This mean that the tube might be in a bad angle and you will need to take a special care to adjust the angle with a double sided tapes. Otherwise the angle will be imprecise and helicopter will always fly rather in a wrong way.

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Spirit System developer