We are using Teensy3.6 in our sensor and we are using battery as a power source. We are supplying regulated 3V from a stable source to Vin pin of Teensy3.6.
Generally it is working fine until sensor is not going to sleep. Problem occur when it is waking from sleep it automatically Teensy3.6 is reset itself. For debugging purpose we are monitoring the reset cause as well as LVD(low voltage detection) of Kinetis K66's core register. From this debug results we came to know that some time it giving low voltage warning detected and some time it reset the MCU. The reset cause we came to know that is reset due to low voltage.

Is there any way to change in Teensy hardware and we can solve the problem of low voltage warning and reset.

To avoid reset the MCU, what should I do? Any help require which can lead us to solve the problem of reset and low voltage warning detected.
@Paul please help or any input will be very good for us.