Tashanwin UPI Verification Fails With Error 140

I am using the Tashanwin application on my Oppo A5 Pro 5G phone, and I am unable to add my UPI payment method because SMS verification keeps failing with Error 140. The OTP is not being delivered to my registered Indian mobile number, so I cannot complete the verification process and add my UPI. This problem started today, the 24th, and for about an hour I have repeatedly tried, but the same error occurs every time. My registered number is +91 99901358** and my UPI name is GAUTHAMKUMAR. Due to this issue, I am currently unable to use or withdraw the 100 rupees I have already deposited in my Tashanwin account. I request that my account be verified manually or that an alternative verification method be provided so I can successfully add my UPI and access my money. I kindly ask you to resolve this issue as soon as possible and inform me about the action taken.