Battery Life for smart Doorlocks

I’m sure the lock is not reporting the battery level correctly. I’ve replaced the batteries two month ago (yes, I use alkaline batteries) and it still reports 99% (as of yesterday). Now, my lock is used a lot - 6 to 10 times a day, sometimes more. I measured battery voltage today and got 1.49 volts on all for batteries, which is around 75% at best.