Me and my husband field a joint federal return and I have it going to my husband's account but now it says it can't be deposited to his account why. Both names on return

Ask the bank why.  Maybe both names need to be on the bank account.   If the bank rejects your deposit the IRS will mail a check to the address on your return. 

What is "it" that says the tax refund can't be deposited? TurboTax? The IRS? The bank?

Did you get the refund by direct deposit or as a check?

What exactly did "it" say? Did it give a reason that the refund can't be deposited in your husband's account?

If it was a direct deposit, and the bank has already rejected it, it's too late to do anything about it. The IRS will mail a check to the address on your tax return. The check will be payable to both of you.