What is your pH? Post that first, pic might help...of the pH comparator during test.
If the sample turns red, pink, or yellow, you are done, your TA is zero (or negative), and your PH is very very low (4.5 or lower).
Use Soda Ash aka Washing Soda. Calculate how much to use using Poolmath. Set pH of 6.8 now and 7.5 as target. Enter 0 for TA. Add amount it states and circulate 30 minutes. Test pH, repeat until your pH is in the 7's, then test TA.