AO tankless no hot water

I keep having an issue where my tankless won’t make hot water. When I turn the faucet/shower to hot, the tankless is still showing that it’s in “standby”. The plumber said to have the gas company check the regulator and meter. They did and said it’s fine and they increased the pressure. If I unplug the tankless and plug it back in I eventually get hot water again. Anyone have any experience in this issue. I recently switched from town water to well water as well but the pressure is the same. The problem also didn’t start until 3 weeks after being on well water.