I suspect that the tip of the thumb-actuated shifter button is worn.
This happened on my 10-speed RH Centaur shifter.
Eventually I had to replace the whole unit, less the brake lever.
@Jon_Mc started
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I suspect that the tip of the thumb-actuated shifter button is worn.
This happened on my 10-speed RH Centaur shifter.
Eventually I had to replace the whole unit, less the brake lever.