Circuit help

I installed a Maestro MS-OpS5M in the bathroom bc my toddler can’t reach the light switch. It controls both the light and fan. I used the 3 way wiring configuration as that’s how the original switch was wired. I initially had to switch the travelers as was directed in the manual. Worked fine. The next day, my husband installed a single pole switch in the garage. The 2 locations are on the same breaker. Now, the bathroom switch won’t work, and 2 other outlets in the living room that are on the same breaker aren’t working. The garage switch still works fine. We bought a new 3 way switch thinking maybe there was a malfunction, but no such luck. I uninstalled the garage switch, but still no success getting the bathroom or other outlets to work. Any ideas on how to fix this, other than needing to bring in an electrician?

Hello Scograd,Thank you for your post! It sounds like the single pole switch that was installed in the garage was wired in a way that it was sharing the incoming "HOT" feed from the breaker to the other locations in the house that are now not functioning. This usually can be corrected with the wiring, however it is difficult to identify exactly what needs to be done through forum posts. We would recommend giving us a call here at Lutron Technical Support (24/7) @ 1-888-Lutron1 (588-7661) when you are on-site for us to attempt to assist with identifying the issue.Hope this helps!-JustinF.