Tritronics flyway G3 battery life

[Sundby]

I have a tritronics flyway g3 2 dog unit and I am not sure if my remote battery is not holding charge or batteries are getting weak, or if it's normal, how often do you recharge your remote? If I fully have it charged I usually have it in my truck use it a few days then recharge it, but recently noticed it basically needs to be charged everynight, what do you do? Thanks