if (distance2 <= 30 && distance2 <= 30) {
I should think that if distance 2 is less than 30 then it is also less than 30.
Can one sensor 'hear' the other? If they are both pointed roughly the same direction then sensor 2 may hear the echo from sensor 1 coming off the back wall long after you stopped listening on the sensor 1 pin. Stick a big delay between the two readings. (Like a hundred milliseconds.)