It seems there are many Bitcointalk members who use TradingView. So I think the problem is the tradingview system detected that you are using fake debit/credit card or you are using prepaid cards(Visa/Mastercard) or maybe they detected that you made multiple accounts.

And actually the weird thing is they only offering 14 days trial, not 30 days. How did you know that they have 30 days free pro trial?

But if you are using real debit/credit card try to contact them instead tradingview.com/contacts/
Maybe the issue is from their system that detected your PC or card as multiple accounts which are not allowed to abuse the free trial.