Tensorflow Install Not Working (Core Dumped)

I've installed tensorflow in ubuntu20.04 LTS, but it has failed.

I'm using a Virtualenv for python3.9, so I use pip command and not pip3

First I upgraded pip, and then I installed tensorflow

pip install --upgrade pip
pip install tensorflow

Then if I open python3.9 and run

import tensorflow as tf

the error I get is

>>> Illegal instruction (core dumped)

Any ideas?