Partial refund payment

 I have only received a partial deposit of my expected income tax refund. According to my records, the IRS approved and have sent the  refund amount of $3,534.24; however, only $1,486.50 was deposited into my account. My refund appears to have been processed through a third-party bank instead of coming directly from the IRS. I've have used TurboTax for years and never encounter this problem before.