The wait block is not working.

I wanted to create the ability to spawn a wall in front of the player. It would act like a shield. However, it should disappear after some time. I made it spawn, and I wanted to set a wait block so that the wall would disappear after 300 ticks. But when I try to do this, the wait block in the code is simply skipped. " Block wait is not supported by the selected generator. It will be skipped "