I have repeatedly, as in almost every day, removed HBO NOW and Netflix from my list of Roku channels only to find them back again. Why?

because Roku units on the same account have a duplicate channel list the first thing to check is your account and make sure that only your units are tied to it 

What he said.

To do this, go to https://my.roku.com/account and scroll all the way down.

As suggested, look at the devices listed. If Netflix, or any app, is added to any one of them, it will add to all of them after an overnight refresh, or after a manual refresh. Likewise, removing it will remove from the others, after a refresh.

If you see any devices you don't recognize, Unlink them. 

If there are no unexpected devices, add a PIN to your account via the PIN Preference setting, selecting "Always require a PIN to make purchases and to add items from the Channel Store." Of course, you may want to do that anyway if anyone else has access to your Roku, or access to any Roku tied to your account.

I do not have a subscription to HBO NOW. It repeated pops into my channel lineup. I remove it and sometimes it pops right back up. How do I PERMANENTLY remove this and several others that I do not subscribe to (netflix, ect) that keep popping into my channel lineup? 

TADEI173 wrote:

I do not have a subscription to HBO NOW. It repeated pops into my channel lineup. I remove it and sometimes it pops right back up. How do I PERMANENTLY remove this and several others that I do not subscribe to (netflix, ect) that keep popping into my channel lineup? 

Change your roku account password and add a PIN number to be able to add channels to your lineup. Likely someone has access to your Roku account that you are unaware of. Sometimes Roku adds channels as an advertisement as well. PIN number stops both situations.