I do not think your laptop is fully charged at 65%. My guess is that is where is sat when you had it plugged in for a while, and you are asking “Why isn’t it charging more?”
Purism allows you to set when your computer will start charging on the Librem 14, and how far you want it to charge to. You can set it for example, to start charging when it hits 30% power, and to “top out” at 90% power.
If your computer has not gone down to the lower threshold, it will not actually start charging higher, even when it is plugged in. If you unplugged the computer, and it went down to the lower threshold, it would start charging again, and would keep charging until it hit the upper threshold.
Take a look at this thread to see how it works.