Virtual background without being set

Someone, I need some urgent help. My Zoom or my MacBook Air is having some troubles. The case is, that the virtual blue color is being set as default background on my video thought I don't choose any virtual screen. Some blur blue color is set on as background, but I want to use Zoom to show around the town as virtual tour, so I don't need any virtual background. 
Would you please someone help what's going on?