I am afraid 8 ppm ammonia, is to high for the tank to cycle.
Try a large water change to get ammonia at 4 ppm. Do not add any more ammonia till you see a drop in the ammonia level. Be patient, it will take a while.
Once ammonia starts dropping, then it is time to start adding ammonia daily. Be careful to not over do it, best to only raise it up to 3 ppm to be one the safe side. Anything over 5 ppm, will kill the cycle.
Once you can bump the ammonia up to 3 ppm and get a zero reading for ammonia and nitrites 12 hrs latter, the tank is cycled.
Then you will need to test for nitrates and do a large water change to lower the nitrates to a safe level before adding fish. My tanks, at the end of the cycle, a 75% water change brought the nitrates down to 20 ppm.
That was a brief description, so any questions, just ask.