Battery problem

[nicnid]

Hello everyone,
I've had this aircraft for two days, and today I'm running into an issue. After about 20 minutes of flight, I lose several systems, including:

The Autopilot
The Autothrottle
The flap controls
The landing gear
The standby attitude indicator

After several attempts to figure out if the problem was on my end or with the add-on itself, I noticed that both batteries are discharging and the alternators don't seem to be providing any power.
Here are a few screenshots from the developer mode to illustrate the problem.

Has anyone encountered this issue before and could help me out?
Thanks in advance!