why no BLE battery level holding for 3 hours only?

[nsureshbvn]

HI, I am using development board of BLE nRF52832 battery which you provide CR2032 is support for good battery backups

please give the reasons behind in it?

[Sigurd]

A typical CR2032 have a nominal capacity of 220 mAh. How fast it will discharge is will depend on what application you are running, and what peripherals you use. If you want to estimate the power consumption, take a look at the nRF52 Online Power Profiler