As no further information has been received regarding your question. Here I am providing information about SharePoint Server recovery of deleted site and method of adding SCA. Hope this helps.
Recover deleted site:
- Check Recycle Bin: Start by checking the Site Collection’s Recycle Bin. Go to Site Contents, press the “Recycle bin” link, and look for your deleted site.
- Restore from Recycle Bin: If you find it, select it and click “Restore”. This will bring back your site to its original location.
- Check Second Stage Recycle Bin: In some cases, SharePoint moves deleted sites to a secondary stage, called “Second Stage Recycle Bin.” Check if your deleted site is here and consider restoring it.
Add SCA to the site:
- Navigate to SharePoint Management Center > Application Management
Site Collections > Change Site Collection Administrator.
- Select the Site Collection to which you want to add a Site Collection Administrator, and select the administrator account.
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