Hello! There is a problem with the behavior of the tail. When I sharply raise the helicopter or lower it, the tail is a little late. That is, the main rotor rises and falls a little faster than the tail of the helicopter. Helicopter goblin 570, no problems with tail stabilization. That is, the problem of stabilization is along the PITCH axis. What settings should you pay attention to first of all? The helicopter is balanced.
When the tail loses its position by giving or taking away collective pitch, the parameter you need to change is in ADVANCED, Setup tab, Tail, and it is "Pitch Precompensation."
You can try copying the Setup you currently use to fly to the other two Setups and then set three different Pitch Precompensation values in the three Setups so that in flight using the three-position switch you use to change the active Setup, you can try three different values and see what for your model behaves best.
Or if you have a radio with a sufficient number of channels you can in ADVANCED, Common tab, Receiver, Calibration Dials section, you can set a radio channel that you don't currently use so that in flight using one of the side Dials on your transmitter you can control during flight the parameter "Tail: Pitch Precompensatiom.".
The PDF of instructions for using the Calibration Dials can be found in the MANUALS section of the software app.
It should be pointed out, however, that before you start using the Pitch Precompensation" parameter, the P and I gains must have already been adjusted to their best. Otherwise, with high Pitch Precompensation values, you would no longer be able to figure out how to properly adjust the tail PID values.
We also recommend checking in the DIAGNOSTIC, Events tab, that there are no n° 106 "Rudder output limit reached" events because in this case it means that the flight controller has already brought the servo that controls the tail blade tilt to the maximum possible excursion (more than that the flight control unit cannot do) but the aerodynamic thrust of the tail rotor is not sufficient to counteract the torque variations generated by the main rotor. In such a case, the only solutions are:
Increase the RPM at which you are flying so that the RPM of the tail rotor is also increased.
If available for the model you are flying with, mount a pulley with fewer teeth (SpeedUp tail gear) in the tail so as to increase the RPM of the tail rotor.
Fit tail blades with higher efficiency. Wider and/or longer. Taking care that when the main rotor flaps backward it cannot get in to the extended tail blades (tails strike). See in the model manual the max tail blades lenght allowed for that model.
