[Resolved]  HDFC Bank — UPI access is blocked

My UPI access has been blocked due to security reasons. this is the second time this has happened in a month.
1st time it was blocked - i visited the nearest branch, submiited the unblock request and it got unblocked.
Now today afternoon i got a message saying that UPI access has been blocked again. i dont understand the reason why it is blocked again.
Last time i visited the branch it was not a good experience. i had to wait for 3 hours to talk to executive and submit the request.
Nearest branch is far away from my place and I do not want to visit the branch again.
this is very very inconvenient and bad banking experience.
I called the HDFC customer care, they were too adman to help or give me the reason and disconnected the call twice.
Please help me out here.
1. nobody is giving the solid reason why the UPI access is blocked.
2. This has happened repeatedly and going to branch is not at all a good experience.
3. Is there any security issue with HDFC bank UPI ?