Turbo tax keeps telling me to revisit box 16 on my 1099-R form however the box is blank on my form

Did you leave it blank, or is there a $0 in it?  If there is a $0 in it, remove it.  This will cause an error. 

If you have state taxes withheld in box 14 and a State payer ID in box 15 the enter the amount from box 1 in box16.

If you do not have state taxes withheld in box 14 then leave boxes 14, 15 and 16 blank (empty)