Rf Scavenger question

I'm playing Pohx build,and now I'm trying to refund the first 4 nodes (dexterity & projectile damage),but it won't work.
I can refund the + 30 to dex and int just fine, but I can't figure out how to refund those 4 starting nodes. Please help me out.

Your passive tree must always be connected a valid starting point.

To refund the first 4 nodes, you'd first have to allocate the nodes you're trying to switch to.

Thanks!