How to makes rotary encoder work only when the other knob is at the certain position?

[stable lily]

I have a rotary encoder and another rotary knob that has absolute position value. I want to be able to increase or decrease frequency on Khz level when rotary knob is at position 1, and change on Mhz level when rotary knob is at position 2. However when I turn the knob Position 1 to 2 and back to 1, it works like toggle and I cant change frequency the way I want.. Is this possible to solve?

[rustic wing]

See this guide: https://docs.mobiflight.com/guides/single-encoder-com-tuning/

While it uses a push button to swap between KHz and MHz the concept is the same

I think your precondition isn't right, look at step 3 in the guide for what it should be