I am installing two single pole kasa smart switchs, side by side

1. one black wire for first swich, other black connect to second swich.

2. other two black wire are wired together, one switch works but the other does not, which is connect to double black wires.

 I installed using the same wires (existing) as discrribed above. which woks on regular swiched, but not for smart swich. How do I fix this, help will be appreciated