When ever I try and redeem my Key it says its invalid, How can I get a new key?

Hi BulbStar

Did you follow these instructions found in the FAQ when you activated the key?

How do I activate my Pyxel Edit license?
Pyxel Edit activation guide
On the Humble download page for Pyxel Edit there is a link named "Click here for your Pyxel Edit key" that let's you claim the license and access your activation key. Copy all the contents of the activation key box (including the "BEGIN" and "END" lines), and paste it into Pyxel Edit when it asks for it.
There has been a problem in some versions where pasting doesn't work, in that case select the key text on the page and click and drag it from the browser into the license box, or paste using right-click and choosing Paste.

I still get nothing, Everything I try tells me the key is not vaild 

Hmm that's strange... you should contact the developer if you haven't gotten it activated yet.
Use this email, then you should get a reply asap: support@pyxeledit.com

I'm having the same issue, will try the same and update back, I just purchased 

Hi. I just bought it and had the same error. I tried activate the app with the key i got from humblebundle. But actually you have to copy that key, (xxxx-xxxx-xxxx) and then click on the link at the top of the humblebundle page (says somthing about activation). And then you can activate it and you get a new key. And that key worked for me and i could activate inside the app! :smile: Maybe that can help you too if you missunderstood like i did first. 
Have a nice day!