If you’re trying to phone one of the missionaries using their cellphone, the numbering system for all cellphones have changed. Here’s an example of the change :
Before – 084 934 1307
Now – 084 9 (84) 341307
Explanation : One must use the second 2 numbers of the area code (ie. in the case of the example above, “84”) and insert them after the “9” (used in all cellphone numbers in Peru). The rest of the number remains unchanged.