W2(12a-12d Codes)

On my w2. 12a code is marked W 1200.00. I am not sure this is correct. I always thought the W is if the employer was contributing and the R was if the employee was contributing. in my case I the employee contributed the whole 1200.00. I received my 1099-SA and in box 5 HSA is marked, but shouldn't MSA be marked. What is the difference between HSA and MSA. So do you think my W2 is correct or do I have to get a corrected W2 the is marked with R in 12a.