Hi leatha129,
We appreciate you reaching out to us. We understand that you are reaching out because your Powerbeats Pro are losing battery charge at an uneven rate.
We’d like to start by setting your expectations. Losing battery charge at an uneven rate is not always an indication that there is an issue with the battery of your Powerbeats Pro.
If your second set of Powerbeats Pro is exhibiting the same behavior as the first, we may have to look into other factors that may cause your Powerbeats Pro to lose battery charge at an uneven rate.
Let's start by resetting your Powerbeats Pro.
Reset your Beats earphones - Apple Support
It may also help if you keep the firmware of your device up to date.
About Beats Updater - Apple Support
You may also want to look into the settings of the device you are using with your Powerbeats Pro.
It sounds like you've already performed some steps to troubleshoot the issue.
If the articles above didn't help, provide us with more details on how you use the device and the steps you've taken, and we'll do our best to assist you.
Take care!