The 1099-SA is issued by the bank or financial institution that administers your HSA. Often, it's the institution that gave you the debit card that you use for medical expenses.
If you had any distributions from your HSA during the tax year (i.e. paid for medical expenses out of the HSA), then you must have that 1099-SA to file. Note that this means that if you didn't use the HSA to pay for anything during the tax year, then you won't receive a 1099-SA and that's OK (you don't have to enter a 1099-SA in the HSA interview if you didn't get one).
If you have the debit card for your medical expenses, contact that bank or financial institution for your 1099-SA. Note that they are likely to have the 1099-SA online.
Otherwise, contact the HR department at your company - it's likely that you are still using the same institution that you were set up with originally.
[Edited 4/2/2020 4:11 pm CDT - improved]
