I first installed this in September, and because this is in use at a vacation home where it is not used often, I didn't realize it but by the end of October the batteries were down to about 65%. What I found though was I could no longer connect to the lock and the last night it connected stayed the same. Someone went to the house early November and the blinking light was no longer blinking. They changed the batteries and it then worked again. They put brand new batteries in. We went there almost 2 months later, batteries were 85% according to app, but I could not connect to the lock. We had to change the batteries again and then it would connect. The lock itself hasn't been used for those 2 months but yet the batteries seem to go down pretty quickly....Could anything else be causing this? I'm not sure whether to recommend or not this product...I like it when it works but not when it doesn't.