We have a Support Tool that will gather relevant information for us to analyze your configuration and logs. Could you please download and execute it on the machine where the stack is running by following the steps described in the guide below?
How to Run the Bitnami Support Tool
Please note that you need to paste the code outputted by the tool in your reply.
Apart from this code, could you please share with us the error message you obtain when running the restart command?
sudo /opt/bitnami/ctlscript.sh restart apache