Welcome in the forum!
Smartsense adapts to changing environment as humidity, aging etc. So it might be that very slow changes are not seen as a keypress, especially when the button layout does not confirm with the recommended pictures.
thanks for your answer,but my PCB layout confirm with the recommended pictures
When there is no bad handling CapSense in the software I would suggest to
- read out the values SmartSense has found for your design and set those manually
- design with CapSense Tuner and use those values (preferred)