In order to view the MMS message, you need to provide the login, phone number and password. Failure to provide any of these requirement, you won’t be able to view.
Quoted from Wikipedia:
NII Holdings Inc. (formerly known as Nextel International) is a mobile phone company using the iDEN standard. NII sells products under theNextel name to Latin American countries. Included are Mexico, Argentina, Peru, Brazil, and Chile.