Is your bike the right size for you?
4" so probably 100mm stem? I'd try a 50mm stem and see how you get on. If you need the bars higher, then get some swept bars.
Yeah it should be the right size as I tried them and got advice in the shop when I bought it. I'm 6'4" but got 1 size down from the largest frame.
I'll try a shorter stem first. I hadn't thought about changing the bars but Ive now remembered that when I was a kid I had swept bars.