Finally -- this is what worked -- it turns out that you need to have your online pandora account associated with your roku -- you don't need to reset the Roku player so ..
1. remove the pandora channel from your roku (Channel Store > select Pandora > remove channel
2. after the channel is removed from your channel list, go back to the Channel Store and select Pandora, then add it back to your Channel Listing
3. You're now prompted to register your roku with pandora -- the roku will show a code to enter in the pandora.com website.
4. register your Roku with Pandora on pandora.com and you are prompted to associate your pandora.com account with your Roku --
5. once your account is associated, channels that you select online will appear on the roku and channels that you create on the roku will show up in the pandora.com list ....Where you can delete them.
I can't believe how long it took to figure this out .... I haven't seen any information that says you need to associate your online pandora account with your roku -- that probably happens automatically for some people who set up their online account first ....or people who have only one account ...
Cheers and happy listening