Log in to your Sinbad wallet
Click on Add money

Select USDT as Deposit method

Copy your Polygon address from Sinbad

Go to Step 2
Log into your Phantom wallet
Ensure you have a USDT balance.
Click on Send

Select USDT

Enter the amount you want to withdraw then Paste the Polygon address you copied in Step 1 above.

Click Send

You’re done! After a few minutes, your Sinbad wallet balance will show your the transfer.