@interrupt EC220-G5 v2 is an ISP tailored device. You should contact your ISP to resolve this issue. That's why you can't find the EC220-G5 v2 in the models list. Although, you can check in your TV...

@mikk97 You should be able to use the WDS feature to have it configured as wireless repeater - use this guide.

@joxojexojaxo The same issue has been reported a week ago. Check this thread and try the suggestions.

@MIOT Lower these settings and test again: Your RE450 has triggered the DoS filtering and the RE450 has been put in Blocked DoS Host List. These could be a false possitives from your AV, make the...

@jwhitte Watch this video for the whole process. It's from Turkish TP-Link division (sorry, couldn't find in English), but you'll easily understand what you need to do. Here's one in in English - its...

Just to add - here's the guide for setting up a guest network on Deco. Check the documents's very bottom notes (in red) for answer on this question.