It is understandable that users may change their mobile numbers (hand-phone numbers) multiple times. If you need to change your number.
You may do so directly in the Seedin App.
Tap 'Profile' Tab at the bottom menu of the App
You would see 'APP Setting, tap on it
You will see your existing Mobile Number and change it in this screen.
Kindly note that on every new number change, you will be subjected to a SMS OTP to verify that the number is indeed with you for security purposes.