I am not sure what you mean "amend HSA to MSA", but I am going to assume that you accidentally made HSA entries in TurboTax and later realized your mistake.
Probably the safest thing to do is to delete all your HSA data and start over. To do this please see the following:
1. make a copy of your W-2(s) (if you don't have the paper copies)
2. delete your W-2(s) (use the garbage can icon next to the W-2(s) on the Income screen
*** Desktop***
3. go to View (at the top), choose Forms, and select the desired form. Note the Delete Form button at the bottom of the screen.
*** Online ***
3. go to Tax Tools (on the left), and navigate to Tools->Delete a form
4. delete form(s) 1099-SA (if one), 8889-T, and 8889-S (if one)
5. go back and re-add your W-2(s), preferably adding them manually
6. go back and do the MSA interview. (do a Search for msa (lower case) and jump to it.)
