I have recently bought 20$ worth of Galaxy Points to purchase from the Artifact Shop a Planet Name Contract. I used it on a planet of mine but the name is not changed on the list, but it is changed when you view it's stats and such.

I was hoping that it would change in the listing too. Is it supposed to or no?

The Planet list data can sometimes be a little older, especially when changing its name or type (such as using an artifact to transform it). The list will update automatically.

a quick way to fix this is to close the GL tab and re-open it, always worked for me to update the planet list.

Concur, the planet list is cached for a little while, prolly for performance reasons. I have yet to see a change actually fail though, a page reload is recommended.

actually, the problem fixed itself over night, the problem is now fixed.