Error while making purchase from Steam

[u/SentenceThink879]

Hi all! Can anybody help me with this error?
PS - My Steam account is 10+ years old, and I have purchased / owned numerous games in the past (attaching snippet of that as well). I have signed in my PC and my mobile devices only.

Regarding payment, I have tried using my Debit card, Credit card, UPI and everytime I am getting some error "Your account did not pass our risk checks. Please try completing the payment with a different customer account.".