@gelngoi ,Earl Samuels , It may be time to replace the battery. Find below a link to a guide and video on how to replace battery, also 3rd link to a replacement battery. Good luck.
I hope this helped you out, if so let me know by pressing the helpful button.
[guide|28633]
https://nobblynoel.wordpress.com/2010/08/27/oral-b-triumph-battery-replacement-video/
https://www.amazon.com/HQRP-Replacement-Battery-ProCare-Toothbrush/dp/B00DOSOM36