SetMototTarget not working

Programming Support ROBOTC Tech Support
1

Im tring to spin a motor 90 degrees and it just spins for like 1 and stops and when I add a wait until motor stop it just stops the code. Im still new to ROBOTC and need help

if(vexRT[Btn8R]==1)
	{
		setMotorTarget(clawMotor, 90);
	  
	}