Error while setting Variable of CTkSlider

[CTRedstone]

Hello everyone,
while I'm trying to set the variable of a CTkSlider (with the .set() method), I get the following error:
"File "/usr/lib/python3.9/tkinter/init.py", line 412, in trace_add
cbname = self._register(callback)
TypeError: _register() missing 1 required positional argument: 'func'"
The error gets raised in the function init of the CTkSlider (in line 105 of the hole file).
I hope you can find and fix this error.

I thank you all for your help,
CTRedstone

PS.: Sorry for my bad English, but it's not my mainlanguage.