I submitted my return on February 15, it says pending, and then under IRS it says unknown if they’ve received it, is there another step?

Pending simply means that your e-filed return is on its way and that the government hasn't accepted or rejected it yet. e-filed returns generally sit in Pending status for 24–48 hours before coming back as either Acceptedor Rejected. Sometimes state returns stay in Pending for several days or even longer.

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