Xfinity Provision

So I have a cax30 and had no issues on the 400mbps plan. I upgraded to the 1000mbps plan and since I get 600-700mbps download and only 5-6mbps upload. I was told the cax30 won’t work on the 1GB plan and since I’ve changed back to lower tier 400mbps plan. 

I called today and was told whatever they did on the provisioning it is stuck in the higher speed and changed settings in my cax30 and a technician needed to come out. 

how can I completely reset and restore everything back to original settings to change whatever xfinity messed up?

Thank you.