Pump runs but no pressure during FW sanitization

[Genr8rs]

New 2023 Bullet bought new on June 24th this year, and when I picked it up the dealer had put in about 2/3 tank of water and demo worked fine. At home and during a short weekend camping the pump ran fine on that 2/3 tank, I did not add any water wanting to say nitize it when close to empty.
After getting home and the tank reading low I decided to sanitize the tank and water lines. I followed the Owners Manual to the letter, not my first RV, I drained the remaining water out of the fresh water tank using the low point tank drain and also the low point drains for the lines. I made the bleach mix and added it to the freshwater tank by the tank fill port. Once the tank was full I then turned the winterizing bypass valve to "on" as directed to bypass the tankless water heater and turned on the pump to circulate the bleach mix through the lines and to the faucets.
The pump ran but no water. and after a period of time as I would open the faucets one at a time, I would maybe get a spit brief small stream of water then just low air pressure. I tried every faucet, toilet and even the reopening the low point drains, and I can hear the pump running but no water flow.
The only change I made was to empty the tank and lines and turn the winterize bypass valve to on as directed. I have not turned the valve back fearing sending bleach water into the tankless water heater. Thoughts?