Cannot restart Nginx after deleting letsencrypt certificate

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My domain is: mobilitytechnews.net

I ran this command: sudo systemctl restart nginx

It produced this output:
nginx[4400]: nginx: [emerg] cannot load certificate "/etc/letsencrypt/live/mobilitytechnews.net-0001/fullchain.p>
nginx[4400]: nginx: configuration file /etc/nginx/nginx.conf test failed
systemd[1]: nginx.service: Control process exited, code=exited, status=1/FAILURE
systemd[1]: nginx.service: Failed with result 'exit-code'.
systemd[1]: Failed to start A high performance web server and a reverse proxy server.

My web server is (include version): nginx/1.18.0 (Ubuntu)

The operating system my web server runs on is (include version): Ubuntu

My hosting provider, if applicable, is: AWS EC2

I can login to a root shell on my machine (yes or no, or I don't know): Yes

I'm using a control panel to manage my site (no, or provide the name and version of the control panel): No (using ec2 instance t2.micro)

The version of my client is (e.g. output of certbot --version or certbot-auto --version if you're using Certbot):

nginx.conf file:

user www-data;
worker_processes auto;
pid /run/nginx.pid;
include /etc/nginx/modules-enabled/*.conf;

events {
	worker_connections 768;
	# multi_accept on;
}

http {

	##
	# Basic Settings
	##

	sendfile on;
	tcp_nopush on;
	types_hash_max_size 2048;
	# server_tokens off;

	# server_names_hash_bucket_size 64;
	# server_name_in_redirect off;

	include /etc/nginx/mime.types;
	default_type application/octet-stream;
	client_max_body_size 512M;

	##
	# SSL Settings
	##

	ssl_protocols TLSv1 TLSv1.1 TLSv1.2 TLSv1.3; # Dropping SSLv3, ref: POODLE
	ssl_prefer_server_ciphers on;

	##
	# Logging Settings
	##

	access_log /var/log/nginx/access.log;
	error_log /var/log/nginx/error.log;

	##
	# Gzip Settings
	##

	gzip on;

	# gzip_vary on;
	# gzip_proxied any;
	# gzip_comp_level 6;
	# gzip_buffers 16 8k;
	# gzip_http_version 1.1;
	# gzip_types text/plain text/css application/json application/javascript text/xml application/xml application/xml+rss text/javascript;

	##
	# Virtual Host Configs
	##

	include /etc/nginx/conf.d/*.conf;
	include /etc/nginx/sites-enabled/*;
}

#mail {
#	# See sample authentication script at:
#	# http://wiki.nginx.org/ImapAuthenticateWithApachePhpScript
#
#	# auth_http localhost/auth.php;
#	# pop3_capabilities "TOP" "USER";
#	# imap_capabilities "IMAP4rev1" "UIDPLUS";
#
#	server {
#		listen     localhost:110;
#		protocol   pop3;
#		proxy      on;
#	}
#
#	server {
#		listen     localhost:143;
#		protocol   imap;
#		proxy      on;
#	}
#}

You've deleted the certificate (why?), but your nginx configuration still requires that certificate. You'll need to fix your nginx configuration to no longer require that cert.

Here you can read nginx documentation

I got this issue resolved by installing letsencrypt certificate again.

Needed to take help from a developer with nginx knowledge.

Please see the https://forum.nginx.org/ for assistance with nginx.