It counts only up

[Barabba11]

Hi, I don't know what is wrong there, if I disconnect one of the 2 inputs I have no events (right), but If I invert them or change rotation it always increase. ON one direction it only increase, in the other if I go really slow it decrease by 1, but suddenly increase by one Which parameter should I change? Thanks

I have ESP8266 and a classic mechanical encoder, I'm using D5 and D6