Going through the https://promotions.t-mobile.com/ParamountPlus site and logging into my account I get a Promo submission page (as seen below).
To move forward on the website and get the offer a promo code is required. Perhaps html of T-Mobile site is broken since this page doesn’t appear to be correct. If page is correct then a promo code is needed (please advise us of this).
Someone else asked this question previously but it was unfortunately marked “solved” despite the response not being valid. I am submitting this thread to hopefully get a valid answer and re-open the discussion.