Anvil bug: Item showing “too expensive” despite no prior work

My diamond pickaxe is showing as too expensive even though it shouldn’t have any prior work on it.

Steps to reproduce:

1) enchant a diamond pickaxe in an un-economical way so it shows as “too expensive”

2) grindstone the pickaxe (this should remove prior work penalty)

3) enchant the pickaxe with a level 30 enchantment (still no prior work)

4) trade with a villager to get a fresh mending book (ie. no prior work)

5) combine the book and pickaxe in the anvil. It shows “too expensive” even though the pickaxe and book have no prior work.

i believe that the issue here is that the grindstone does not remove prior work, but it should. Could be an anvil issue though.