Roku should not have released the Express 4K+, it simply does not work.
A dozen attempts over one hour all failed. I tried every tip from the Roku forums and YouTube, none of them worked. This product just does not work. I'm returning it, with prejudice.
I've owned several Roku products for over 8 years, I've never had this much trouble pairing the remote. It usually pairs immediately or pairs with a little finagling. Earlier products were so much easier to set up than the Express 4K+; Roku has seriously regressed in that respect. Very disappointing.
This experience has really damaged my perception of Roku and its products.