My Box 17 St Tax WH on Form 1099-INT (DISCOVER BANK) is empty, but TurboTax require me to fill an input

If I didn't input this, I can't file electronically, but my Box 17 St Tax WH on Form 1099-INT (DISCOVER BANK) is empty, noting. Turbo tax said "Form 1099-INT (DISCOVER BANK): Box 17 St Tax WH - Line 1 should have a value if the state identification number has a value.". what should I input? I hope to finish and file electronically