I'm going to keep this simple to make sure everyone reads this.
Playing multiple saves or multiple households in one save may result in a Bills data reset. If you stay in one save-one household it should not reset. We plan on updating this mod once more next week after the Holidays.
In the meantime, you can play without the mod and start afresh once we've updated the mod or set up Bills in one household then save once set before moving to another household in the same save.
If you come to support about a Bills resetting after updating to version 0.4.6.1, we will refer to this announcement again.
-Nichole