As a Marketplace Owner, you will be able to control which organisations are on the marketplace. You can simply set this in the configuration if Active automatically is set to Yes. This is found in Stores > Settings > Configuration > Omnyfy > Organisations.
Approving an Organisation
As a Marketplace Owner, log in to the back end.
Go to Customers > Organisations > Organisations Management.
Here you can view all your organisations. You'll be able to see all of their statuses as well. Look for the organisation you'd like to approve (they should have a status of Pending), and choose Edit.
Once done, then simply set the status from Pending to Active.
Once this is set to Active, choose Save Organisation from the top right. The organisation will now allow all customers registered under it will be able to purchase from the marketplace.
Deactivating an Organisation
You can deactivate an organisation by going to the admin as a Marketplace Owner, and going to Customers > Organisation > Organisations Management
Find the Active organisation, and choose Edit.
Select the status dropdown and change it to InActive.
Choose Save Organisation from the top right.