Who’s plugin are you using and where are you trying to put the code?
I have the same issue. The name of the plug-in IS adsense-deluxe.
Just to share, the keyword is the “name” of the ad and the problem appears to be using non-alpha characters eg. numbers. I had named my first ad google1 but it wouldn’t save. Why it’s called keyword in the error and name in practice I’m not sure, but it can be confusing.
I found that if I write for example “adsense left side” in the NAME section, the word “adsense” is not accepted.
As soon as I take it off, I am fine and the adsense block is created.
Hope this helps. (Took me an hour to figure it out!)
