They dont accept Postal Id. She need to bring her SSS ID, Drivers License, Voters ID, NBI Clearance. If she has just only NBI clearance, she will need to produce more supporting documents. I cant understand why they dont honor the Postal ID as it is a government issued ID.
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If she is a registered voter but does not have a ID she will need to bring her voters tab or voters registration.
Yearbook when she graduated, and yes diplomas will help also.
If she has land under her name or business she need to provide that also. And an ITR.
It is better for her to also submit some western union or any money transfer receipt stated her info such as name address and birthdate.
Ohh and police clearance also...
Applying passport here is like applying for a visa now
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If she does not have that required ID's....