A number, campaign, customer, or integration resource belongs to its own project. Selecting another project changes the view; it does not copy resources into that project. All projects combines only the views that support a team-wide listing.
Check the selected team and project against the resource's known location. For an integration, also check which project its credential can access. Do not replace identifiers with resources from another customer's workspace. If the resource was present in this project and has disappeared, report when it was last visible and the relevant page, without sharing keys or private customer records.