When you create a ShapID for the first time, no matter at which participating bank, this will be seen as your default ShapID. At Nedbank your ShapID will be the same as your primary cellphone number, eg 083 123 4567.
Once a default ShapID has been created at, for example, Nedbank, if you create a ShapID at another participating bank, the ShapID will have the domain name of that bank, eg 0831234567@BankB, this will be to differentiate between the different accounts that are linked to the ShapIDs.
When you want to receive a payment to your ShapID (cellphone number), you will share this with the person who is paying you.