First thing we recommend trying is a clean reinstall of the Spotify app. Make sure you perform this on both your own mobile device and your wife's. This will help in case the issue is related to corrupted cache. Then make sure everyone logs in using their correct account details.
In case the issue persists after running a clean reinstall, try disabling any battery optimization settings or data cleaning apps that run active on the mobile devices. Such features can often prevent Spotify from operating at full capacity. We also suggest accessing the app settings and making sure all Permissions are enabled for Spotify.
Keep us posted! We'll be happy to lend a hand if you need more help.