It works fine when the battery is plugged in, but when running on battery mode, the PC shuts down without even warning. 
It never happen before until I installed Manjaro. By the way, I have tried every little thing on the Settings/System panel, no luck though...

cat /etc/lsb-release:
DISTRIB_ID=ManjaroLinux
DISTRIB_RELEASE=20.0
DISTRIB_CODENAME=Lysia
DISTRIB_DESCRIPTION="Manjaro Linux" 

xfce4-power-manager --version:

Xfce Power Manager 1.6.6
Part of the Xfce Goodies Project
http://goodies.xfce.org
Licensed under the GNU GPL.

Some info about my PC:

lscpu:
Architecture:                    x86_64
CPU op-mode(s):                  32-bit, 64-bit
Byte Order:                      Little Endian
Address sizes:                   40 bits physical, 48 bits virtual
CPU(s):                          4
On-line CPU(s) list:             0-3
Thread(s) per core:              1
Core(s) per socket:              4
Socket(s):                       1
NUMA node(s):                    1
Vendor ID:                       AuthenticAMD
CPU family:                      22
Model:                           48
Model name:                      AMD A8-7410 APU with AMD Radeon R5 Graphics
Stepping:                        1
Frequency boost:                 enabled
CPU MHz:                         1131.669
CPU max MHz:                     2200,0000
CPU min MHz:                     1000,0000
BogoMIPS:                        4393.10
Virtualization:                  AMD-V
L1d cache:                       128 KiB
L1i cache:                       128 KiB
L2 cache:                        2 MiB

Some from my battery (you'll see it is plugged in):
upower -i `upower -e | grep 'BAT'`
  native-path:          BAT1
  vendor:               131-42-6E
  model:                HS04041
  serial:               44933 12/08/2015
  power supply:         yes
  updated:              sáb 16 may 2020 09:51:49 (71 seconds ago)
  has history:          yes
  has statistics:       yes
  battery
    present:             yes
    rechargeable:        yes
    state:               charging
    warning-level:       none
    energy:              19,0092 Wh
    energy-empty:        0 Wh
    energy-full:         26,134 Wh
    energy-full-design:  25,8566 Wh
    energy-rate:         5,9422 W
    voltage:             16,706 V
    time to full:        1,2 hours
    percentage:          73%
    capacity:            100%
    icon-name:          'battery-full-charging-symbolic'
  History (charge):
    1589615509	73,000	charging
  History (rate):
    1589615509	5,942	charging


Can someone help me? What can I try?
Thanks...