Users sees "Access Denied" after two seconds in SP site

Hello,

We have four team site in SP. We set up all sites with same futures but share to different security groups. Only one site has problem about access... 

"Operation Team" security group is member of Site Visitors Group and has Read permission. They can open company home page then. they can click site links in web part (promoted links).

Sites are Cloud, Managing, Reporting and Project.

Cloud site can open then just 2-3 seconds later site refresh and. "Access denied" page come.

I check all conversations. I checked all setting but can not solve. Also I compared other 3 sites settings. Everything same but only Cloud site has "Access. denied" message some seconds later.

Any ideas??