i have add subdomain but it not work how to solve it

first you need to access your register domain account

domain name records called (DNS record ) show one main domain with add DNS A record

all domain or subdomain  required to point with host
A record point to your hosting server

step 1 : create sub domain in hosting cpanel

step 2 : goto your domain register account
step 3 : goto DNS zone file

showing example is godaddy cpanel

  


your host name is subdomain name

Host -> subdomain name
Point to -> server ip

TTL use default or custom