Cyfeiriad dychwelyd mail receipt section dgfe

I think you're asking for the return address to send a mail receipt in Welsh!

In Welsh, the phrase you're looking for is "Cyfeiriad dychwelyd: Adres y cyflenwad" which translates to "Return address: Address of the supplier".

If you're looking for a specific format, you can use the following:

Cyfeiriad dychwelyd: [Supplier's Name] [Supplier's Address] [Postcode] [Country]

For example:

Cyfeiriad dychwelyd: Amazon UK 30 Victoria Street London SW1E 5AH United Kingdom

Please note that the format may vary depending on the country and the specific supplier.