Hi there!
Usually the pin that the servo uses needs to be a PWM pin. Pins 1 and 2 are usually not PWM pins, which would indicate the issue.
There are some boards like the Arduino Mega that have PWM capabilities on these pins. Can you tell me what board you are using?
As others have said, it is usually not the greatest idea to use the Tx and Rx pins (1 and 0) as signals unless necessary, as it can add problems.
That being said, try returning to pins 9 and 10 for the two servo signal pins with your modified code and see what happens!
Good luck 