what to do if moudle not in pip3 only in pip2?

[korenron]

 python3
Python 3.7.3 (default, Jan 22 2021, 20:04:44)
[GCC 8.3.0] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>>

python3.7
Python 3.7.3 (default, Jan 22 2021, 20:04:44)
[GCC 8.3.0] on linux
Type "help", "copyright", "credits" or "license" for more information.

 pip3 install modem-cmd
Looking in indexes: https://pypi.org/simple, https://www.piwheels.org/simple
Requirement already satisfied: modem-cmd in ./.local/lib/python3.7/site-packages (1.0.2)
Requirement already satisfied: pyserial>=2.6 in /usr/lib/python3/dist-packages (from modem-cmd) (3.4)

same error:

python3.7
Python 3.7.3 (default, Jan 22 2021, 20:04:44)
[GCC 8.3.0] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> from modemcmd import modemcmd
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/home/pi/.local/lib/python3.7/site-packages/modemcmd/__init__.py", line 2, in <module>
    from serial import Serial
ModuleNotFoundError: No module named 'serial'

I have try to reinstall serail\pyserial - but it said thery are there

pip3 install serial
Looking in indexes: https://pypi.org/simple, https://www.piwheels.org/simple
Requirement already satisfied: serial in ./.local/lib/python3.7/site-packages (0.0.97)
Requirement already satisfied: iso8601>=0.1.12 in ./.local/lib/python3.7/site-packages (from serial) (0.1.16)
Requirement already satisfied: pyyaml>=3.13 in ./.local/lib/python3.7/site-packages (from serial) (6.0)
Requirement already satisfied: future>=0.17.1 in ./.local/lib/python3.7/site-packages (from serial) (0.18.2)
pi@raspberrypi:~ $ pip3 install pyserial
Looking in indexes: https://pypi.org/simple, https://www.piwheels.org/simple
Requirement already satisfied: pyserial in /usr/lib/python3/dist-packages (3.4)