Materia help

[MystinaValeth]

You can't meld material if the materia is a higher level then the level requirement for the equipment (ex: can't meld tier IV materia on a level 30 belt). Also, make sure that type of equipment (body, head, legs, etc) can support the type of materia you're trying to meld. You also can't request for materia meld through bazaar if the gear is already melded (it can only single meld, not double).

Could one of these be the reason it's not working for you?