Putting Frost Walker on enchanted boots via Anvil doesn't work

I tried putting the FrostWalker2-Enchantment (from enchanted book) on a pair of enchanted boots and it didn't work.
The enchanted book disappeared and all other enchants (Unbreak. and Protect.) on the book appeared on my boots just fine except FrostWalker.
I tried the same thing with unenchanted boots and everything worked fine,
so i assume its just with enchanted boots.
I play on an online server currently on Minecraft version 1.11, I didn't try it on other versions.