Install a renewed SSL Certificate in a AWS EC2 Linux Instance

My web app stopped being able to retrieve data from a table because a third party SSL installed in a EC2 Linux instance expired. I renewed the certificate and have the private key (.key) and intermediate (.cer) files. I managed to move the new files to the EC2 nginx folder. However it didn't work. It seems like nginx service needs to be restarted or my bundle.cer didn't work.

I need someone with AWS administrative experience to fix this for me.

Thanks