Are you sure you are calculating the standard deduction correctly? It should be 15% of your Maryland adjusted gross income as listed on line 16 of your Form 502. However, it is a minimum of $1,700 and $3,450 and maximum of $2,550 and $5,150, depending on whether you are filing single or married-joint. Per the instructions for MD Form 502:
MD Form 502 Instructions
You can use the standard deduction worksheet on page 12 of the instructions to get an accurate calculation of your standard deduction: