By design, currently Refund Genie and the Helium 10 tools in general will work with 1 Amazon seller account only. Whichever seller account you connected to your Helium 10 account and ran Refund Genie with, the tool will remember that and will always pull up data from that account. Changing the connected Amazon seller account will not change the source from where Refund Genie gathers data. We also discourage from changing that connected Amazon seller account as this may just cause issues on keywords being tracked in Keyword Tracker or ASINs being monitored in Hijacker Alert.
If you have more than 1 Amazon seller account, we advise to please have a dedicated Helium 10 account for each one of them. You can always check the amount that Amazon may owe you for free. If the amount that Refund Genie shows is enough to justify a subscription, then it will be your decision after if you would want to subscribe to a plan for your 2nd Helium 10 account.