IRS says the amended tax refund has been completed 3 days ago, but actually not received

I received a notice from IRS that my amended tax return has been approved and i should receive my return in 2-3 weeks. Today I query the status from IRS website and it says the refund has completed 3 days ago and I 'should have received the refund'. But actually, I don't receive anything. Does anyone know this situation and tells how long will the money appears in my bank account? Thanks so much.