If you are collecting sales tax from customers - you are acting as an agent of the state DOR - and sales taxes you are collecting do not belong to you in first place.
The bad news is that there is no statute of limitation on sales tax collection...
The best you may expect - that the DOR will drop penalties if you provide a "good reason" why you was not able to remit sales tax.
Ther e will also be interest charge on late payment - and it is very unlikely that the state will forgive the interest.
Another bad news is that all states are short of revenue and are now very aggressive in collecting...
South Carolina DOR runs ongoing tax relief program to out-of-state businesses who have not filed or have not paid their SC taxes and have not been contacted by SC DOR.
According to the program - DOR waives penalties on the condition of full payment of taxes and interest.
Let me know if you need any help.
Tax Preparer
Taxes, Immigration, Labor Relations