Developer mode not active

I have been studying about Roku applications, however I am having difficulty activating the developer mode and testing my applications on my TV, I need an answer if my TV is on a BlackList, a while ago when I bought the device I installed a third party application and after that I no longer get my access, I need the release to continue my new project to develop my website application for ROKU devices that I see great potential.

Sincerely,
Jaylan Santos,

I look forward to hearing from you.

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