Bike Sizing/ Advice

Hello, I recently purchased a CUBE Agree with 56cm frame. I’m 179cm Tall and an inseam of 84.5cm.

And I’m now starting to think the frame is too big.

Should I size down? Would a 53cm frame work better for me or would I feel more cramped?

I think the problem is my reach but not too sure.

Any advice would be greatly appreciated.