zwift can't paired with speed sensor but pair with a power source which I don't have

 after the recent Zwift update it can’t paired with my speed sensor, it was working fine the last two years.  I am using an Iphone with 4iiii hrm to connect garmin speed sensor and garmin cadence, on a classic rollers.  With the recent update zwift can only paired with HRM and Cadence but when it come to the power source or speed sensor selection it cannot find the speed sensor but it paired with power source instead.  I don’t have a power source!  I have disconnect and close my 4iiii app on the iphone.