Same issue here! Prepared all my taxes to go over them yesterday and then. Boom I coudn't file my MD state taxes due to this error. I gave up at 1 am. Knowing I am now too late anyway.
I will held Turbotax responsible, they could like Federal just file it at no cost, but with all there ads in the the software itself, they try to make an extra buck instead of focussing on reliablity.
Now I am might facing a penalty and/or need to file by paper. lets see if they call me back today. The wait times were greater than 1 hour. Godsake I am not the only one.