Problem with mysql
Introduction
There are some situations where you could face issues in saving data either from forms or any other medium, these issues are basically caused by mysql.
Solution
If you have modified your mysql configurations then you need to check those and if not check the status of mysql server by using the below command.
sudo service mysql status
If you see the status inactive then your mysql server is not running so try to restart it by using below command.
sudo service mysql restart
If this doesn't solve your issue then try to use migrations on which database of LMS and CMS relies on. Run the below command as edx user to migrate the database.
source /edx/app/edxapp/edxapp_env python /edx/app/edxapp/edx-platform/manage.py lms makemigrations --settings=aws
python /edx/app/edxapp/edx-platform/manage.py lms migrate --settings=aws
python /edx/app/edxapp/edx-platform/manage.py cms makemigrations --settings=aws
python /edx/app/edxapp/edx-platform/manage.py cms migrate --settings=aws