I've included a link to a gentleman that does a great job explaining the Aqua-Hot functions and some troubleshooting that may be of help to you.
I'll go out on a limb here, and apologize in advance if I seem presumptuous but... I see you have 5 Posts, and joined in 2/2020, is the Coach new to you, if so...
Is your Vega-Touch set up properly, i.e., are you on Manual or Schedule. if Schedule are your settings at the proper limits. Are you using the Heat Pumps in addition to the A/H, although below ~ 40 degrees they will not be effective.
Have you called the service provider that did the Service and ask them to walk you thru some troubleshooting options, it may be a simple fix, disconnected/loose wire/s etc.
If it had worked properly prior to the service, and now after the service does not, I would start there.
Hopefully others will respond with additional ideas and/or advice.