Nextcloud problems / questions

Do I need to run the Certbot multiple times after each other for the main domain and seperate for the wanted subdomain?
Or run it just once with the main domain and wanted subdomain seperated by , or ; ?

I get this error running the Certbot by DietPi-LetsEncrypt ‘nextcloud.YourDomain.com

[FAILED] Setting was found multiple times 
The pattern $1 
server_name[[:blank:]]  was found multiple times in file $3                                                                                  /etc/nginx/sites-available/default 
7:        server_name YourDomain.com;  
49:        server_name YourDomain.com;
   
Either the pattern $1 needs to be more specific or the desired setting can appear multiple times by design and it cannot be predicted which instance to edit.  
Please retry with more specific parameter $1 or apply the setting manually:         
server_name nextcloud.YourDomain.com;

?