Whoop lift off

I am new to FPV, got a couple of digital whoop the Alfa A75 and Rocket light, put them through the set up on beta flight, they are Bind and fly. Anyway, to held the drone to see if the if the stick on the remote worked, when I throttled, I could go half wave and bring it down, when I push it all the wall forward, the drone stayed at high throttle and I couldn’t slow it by bring throttle down had to use dead switch. Did this withe both whoops, so now I am afraid to try them out side do lose the, any idea why this happen. Could it be the motor stay on high because the drone is trying to gain altitude and it can’t because I am holding it down, but this are not gps drone, help?
Thank, Don