I am unable to allocate Mailbox quota for my domain and its showing “Only 0 space available “

Solution :

To resolve this issue you need to allocate the resources for all your domains within the resources allocated to your whole reseller account .

Please find the below procedure to sync the Service Plan in Plesk Control Panel

[1] Access your control panel at https://www.yourdomain.com:8443 [ Example :https://www.servername:8443 ]

[2] Click on subscriptions.

[3] Click on the subscription name.

[4] Click on sync option.

This will list the parameters which you need to reduce in your plan or service plan. Change the same in your plan and again click on sync.