I'm android users too, when i'm with Nexus Phone the time.. everything works as advertised...
thing changed when i switch my phone to LG V30+, the LG phone tend to put everything related to Bluetooth into deep sleep after a while which caused the Sesame is not auto unlock when i'm back to my house! I had the same put GPS enable and NO BATTERY SAVING AT ALL TO MY SESAME APP. still is same result.. LG putting the bluetooth to deep sleep when there's no activity.
i need to eventually turn on my phone and wakes the bluetooth manually to auto unlock the sesame.
it's been like that for 1 year for me until i switch my phone to Samsung S20 Ultra. while Samsung didn't do deep sleep for my Bluetooth and thus, my sesame lock is back to normal state every time when i get back home.
so before you really put a blame to sesame.. you should check is your phone putting your bluetooth to deep sleep or any other related services to deep sleep.
just my 2 cents.