US OBLIGATIONS for State tax??

Hi, I'm trying to complete my Maryland State tax return using Turbo-Tax premier. I have some stock/bond investment profits from a successful trade I executed in 2020. Turbo tax says:
"You can exclude capital gains from US Obligations because Maryland doesn't tax them. Enter any portion of your capital gains that came from US obligations."

Federal Total = $2696    Total from US Obligations = (blank space waiting my entry)

 

I looked all over my Vanguard tax forms including the 1099-B which lists this trading profit. No where does it mention "US Obligations", although I know the mutual fund I was invested in contained about half bonds, man of which were govt bonds. The other half were US equities.  The shares I traded was a Vanguard mutual fund called VTMFX.

 

Also, I am filing as a part time resident in Maryland this year. I moved out of state to South Dakota less than 6 months through the year. I realized these profits well after I left Maryland on October 29. So I would think the capital gain would not be taxable in Maryland anyway.

 

Can someone advise me on how to handle this entry?

Thank you