American immigrant visa inquiry

Excuse me, does the invitation mentioned in your question refer to immigration application? If so, your application depends on the timetable. You can go to www.uscis.org for inspection according to your priority date.

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If your mother is a green card, your application belongs to relative immigration. There is usually a waiting period of 4, 5 or even longer. It is normal to have no news for two years. Wait patiently!