He was feeding on live rodents. Are you offering that or trying to switch to frozen thawed during this time. You have had him less than a month and are already trying to feed while trying to acclimate. Not the best idea.
First I would hold off feeding until you meet the husbandry conditions needed to help this snake reduce moving stress and feel safe in their enclosure.
After meeting the requirements you need to for a ball python, I would then offer only once per week a live or preferably pre killed (as in you buy it live and kill it right before offering) until this snake starts eating. After getting it on a reliable feeding schedule where it does not refuse and where its husbandry needs are met you can then try and switch to frozen thawed.
For now I would reply to Deborah in this thread. She has the experience you need to get your snake feeding and as such do exactly what she says. Do nothing else until you fix husbandry to what your snake needs. Stop trying to feed so much and give it a week at least to acclimate before offering again.