Cannot lock current layer

[gogamid]

"The bottom row index and middle column keys are used for layer lock. Index is for the current layer. Middle is for the opposite layer (normally activated with the corresponding primary, secondary, or tertiary thumb key on the opposite hand) and can be used for single handed lock and layer use."

I am able to lock the opposite layer, but locking the current layer doesn't do anything. How I do it:
I have mouse layer on the left side which is activated by holding right primary thumb key. If I want to lock mouse layer, I am still holding the right side primary thumb key and then tapping twice bottom row index. But this doesn't lock the mouse layer.

[manna-harbour]

See https://github.com/manna-harbour/miryoku_zmk#no-current-layer-lock.