• Author's solution is wrong
• No random tests
• Duplicate: https://www.codewars.com/kata/hex-to-decimal

You just published an exact duplicate to your own kata (including the duplicate issues), which is already a duplicate of others.

Essential reading for new authors: https://github.com/codingforeveryone/READMEs/blob/master/codewars/writing-your-own-kata.md

Many issues with this one, but the most prominent would be that it's a duplicate (in the sense that you just have to check if a string ends with a specific substring).

Other issues:

• initial setup has the test assertions where the user's code goes
• no random tests

Please keep these things in mind when you think about writing your next kata.