Roller marks on an old previously painted ceiling, using PBW Matt

As the title says^

When natural light enters through the windows, I can see many roller marks on my ceiling.

It's not a newly plastered or skimmed ceiling. It's previously been white before.

I'm using PBW Matt one coat by dulux.

I'm using a good quality Harris roller and sleeve.

I'm rolling parallel too the window.

Should I now roll at a 90 degree angle from the window?

Should I thin the paint?

Thanks in advance.