Contact the manufacturer's tech support.

(should be an automatic step for problems like this, for any kind of product)

"I cannot get it to switch back to the internet port"

I don't understand what you mean.

The TV is now connected to the Internet via the Cat6 Ethernet cable which, I presume, is connected to your router. You now can use the built-in Roku. What's the problem?

The problem is that I can't use the build-in Roku without signing up for their service, which isn't free. If it were free, why are they asking me for a credit card number? It's just like Apple - they want to be able to be able to charge you.

Try this*:

1. Browse to roku.com

2. Click 'Sign in' from the top menu.

3. Click 'Create account' button.

4. "When you are registering on your computer once you reach the credit card number dialog box there is an icon that says skip in the right-hand corner of the screen which will allow you to skip this process." -- Source

*I didn't test this as I have no need for a Roku account.

There is no fee to get a ROKU account. They do require a credit card to activate the device - but (again) there is no fee to activate the device. Channels that you install may require a (monthly) - Hulu, Netflix, etc. fee. I have a few services, but pay the service (not ROKU) separately. I have 4 ROKU devices, I only had to provide credit card info on the 1st device. As an aside, the card I used has since expired and ROKU has not asked for updated information.

Two questions to Lawrence and Mike. I don't want to give my credit card info to any company from whom I don't intend to make any purchases, BUT, if I do get the Roku account, can I use it to pay for Netflix, etc.? I also have a Samsung TV which also has internet and I can access many free sources on line, and also paid services such as Netflix (if I have an account).

For billing through ROKU, check out this - https://support.roku.com/article/208756478-how-to-manage-or-cancel-a-subscription-to-a-channel. I have never paid a penny through ROKU services. My Hulu and Amazon Prime are paid separately at my convenience. I can select HULU, Netflix, Amazon Prime through my SmartTV, but have chosen to use my ROKU. There are some differences in capabilities of each device, IE my ROKU stick is capable of streaming 4K, the SmartTV isn't. Youtube is presented differently on the SmartTV VS the ROKU stick.

1. You can add your "streaming device" to an existing Roku account. So you can add your TCL TV to your Roku account and you can add your Samsung TV to your Roku account if you buy a Roku Player for it.

2. You can purchase channels such as Netflix from your Roku account both from your "streaming device" (e.g., TCL TV) and from your computer. Of course, you must have set up a payment method in your Roku account to do this.

I've had a Roku for quite some time and I don't remember providing credit card information to get it to work. I do have a Roku account and password, but I think its just used to add channels to the Roku. All my payments go through Netflix, Amazon Prime, Plex, etc.

Bruce