Issue with email links

I have self hosted ERPnext and all working fine. However, emails links (Eg, user password etc) are sending with port and it is not working then.

Nginx conf is configured to use domain name “erpdemo.uti.com” with proxy “proxy_pass 0.0.0.0:8000;”

A sample email link sent is below.

erpdemo.uti.com:8000/update-password?key=zFSvCa6jj21ykuR4FGBzPHscLRbc6Cf0

How can we avoid this port in place while sending out emails?

I have tried frappe-bench/sites/site_config.json with hostname but no joy.

How can we fix this email sending issue? It needs to go without port?

Thanks fro the help