Dealing with shuttle falling vertically down

This has been a perplexing issue for me for more than a year.

If my coach gives me a shuttle that falls vertically down, I will make all kinds of errors.

For clears, I either mistimed my hitting, most of the time striking near the top of the racket. Either that, I will slice the shuttle when clearing back, and most of the time I sliced it towards the backhand corner of a right hander. The end result is a very bad clear, either ending at half court or if it goes far enough, it becomes a smashing opportunity.

For drop shots and smashes, I couldn’t make them go down at all. They are all fairly flat and slow. My coach has said that it’s because I’m taking them too low. I’m aware of this as I wanted to strike near the sweet spot, but always gets them wrong and ends up striking near the bottom of the racket or hitting the T-joint of the racket. For smashes, I will also slice them and the shuttle ends up in random places. If I adjust to take them higher, then I will face the same problems as clears -_-.

My coach said he hasn’t seen a problem like mine, particularly the clearing issues because everyone could just hit a clear at that angle. He didn’t say anything about the drop shots and smashes. I think it’s because it won’t be easy to make the shuttles go down at that angle.

My coach has adjusted tons for me but no improvements. I have also tinkered with various hitting angles but to no avail. Also hung a shuttle on the ceiling simulating the vertical drop and tried to hit it, but same errors.

I am out of ideas. Does anyone know what I can do to improve the situation?