How to Change Mobile Number in UPI | Apna Number Badley Aur UPI Se Jude Rahe | UPI Chalega

I have a bank account linked with one mobile number. This is a newer mobile number, but the UPI is also working on my old number which I was using previously. Why is this happening? I AM straggling help me any one

I have a bank account linked with one mobile number. This is a newer mobile number, but the UPI is also working on my old number which I was using previously. Why is this happening?🤔. In my understanding it should not be like this.