My copter can't fly in Attitude Hold well. I need help

I use
FC: Kakute H7 mini
ESC: hobbywing micro 60a 4in1
Motor: Brotherhobby avenger 2806.5-1700kv
Prop: 51466
Battery Lipo 6s
Firmware: ardupilot copter 4.3.3
Total take off: 2-2.1 Kg
I use Inital Paramater Setup to set my copter. However when I fly AltHold mode my copter can’t take off. I change MOT_THST_HOVER from 0.2 to 0.52. My copter can take off in AltHold but it can’t hover and slowly landing when Throttle stick still up. Anybody have solution ???

It’s only conjecture without a .bin log, but trying to lift 2+ kg with those props and motors sounds like a tall order…

To echo what Yuri_Rage says, I predict for 2.1kg you will need props twice the size and motors half the KV, or twice as many.
If using a BLHELI ESC set
Low RPM Power Protect = off