Rune Page Bug (Cannot create a new rune page)

Here's a step by step of how this issue happens.

1. I log into the game.
2. Click on Collection.
3. Click Runes.
4. Click Create New.
5. I pick a Keystone.
6. After picking the keystone, I get the little X symbol and nothing is created.

The client says I can make one more page. Considering I only have premades and one custom page, this looks like a bug.