You will need to ask the sender to confirm that the transfer details match the details of your Magenta Pay account.
The details shown in the transfer confirmation must fully match those registered in your Magenta Pay account. Transfer fees have to be set to 'shared' (SHAR/SHA).
You can also contact the sender to find out whether the transaction has failed and the money has been refunded. Sometimes failed transfers arrive in the bank's system, but are not credited to the sender's bank account immediately.
If you have not received a transfer, check whether the required period has elapsed.