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Open “Studio Managers“ page;
https://sitename.com/exec/manager/managers
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2. Click by studios count link which you need https://sitename.com/exec/manager/performerstudios?manager_id=3&manager_name=radultusername;
3. Select other managers for selected studio and click by update button. Or delete studio;
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After this, you can delete
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“username“ manager here: https://sitebame.com/exec/manager/managers