C5 Ultra lags and slows down when battery is low like below 20%

Hi, got the C5 ultra a couple of days back. I feel that my phone slows down and lags when the battery is low? Its almost unusable due to the lag in the app drawer and recents panel. Im not sure if this happens everytime the phone is low on battery. Is this is problem for u as well and is there any fix?
Thanks