A colleague mentions a page you can't find, or a link someone sends you bounces straight back to Home. There are only a handful of reasons this happens, and they are easy to tell apart. Work down this list in order.
First, check it isn't just folded away
Several sidebar entries are groups, not pages: Performance, Calls, Operations, Scheduling and Human Resources each hide their pages behind a chevron until you click the group open. The whole sidebar also collapses to a strip of icons — the arrow at the top toggles it, with a tooltip reading "Collapse sidebar" or "Expand sidebar" — and while collapsed, hovering a group icon pops its pages out to the side.
Your access was limited by an admin
Every admin account has a per-page access list. You'll find it under Settings → Users, in the Administrators list: edit an admin and you get a section headed "Access" with a checkbox for each area — Scorecard, Chat, Incentives, Payouts, Rostering, Settings, AI Agent, Incidents, Fleet, Drivers, Recruiting, Payroll, Timesheets, Billing, Scheduling and Reporting. A checked box means allowed. As the help tooltip there puts it, "Specify what your admins are allowed to view," and "Admins with access to Settings can add or delete other admins."
How you recognize it: the entry is simply absent from your sidebar with no explanation, and pasting the page's address into your browser sends you back to Home. It also thins out things inside pages — a driver's profile only shows the tabs your access covers, so someone restricted from Scorecard sees no Scorecard tab on any driver.
Watch out for one box covering several places: "AI Agent" governs Viki's own section, all the Calls pages, Dispatch and Route Assistance together. If a page you need is missing, ask whoever manages Settings at your company to check the box for you.
Some areas only the root admin can hand out
Four of those checkboxes are locked for ordinary admins: as the same tooltip says, "Only the root admin can modify access to Payroll, Timesheets, Billing, Reporting." New admin accounts start out without those four, and another admin with Settings access will see the boxes grayed out and won't be able to help. The Type column in the Administrators list tells you who to go to — the account marked Root is the original admin created when your company was set up, and it's the only one that can grant those four. That row also can't be edited or deleted by anyone from the app.
Billing behaves slightly differently again: it disappears from Settings when your company is invoiced manually rather than by card, because there'd be nothing on the page to show you.
The feature isn't switched on for your company
Plenty of sections only appear when the matching feature is enabled for your company, and that switch lives with VoiceERP rather than in your settings. Human Resources shows up only if Incidents or Recruiting is on for you. Netradyne, Quality and Shift Confirmations each appear under Calls only when that feature is on. Operations needs at least one of Rostering, Fleet, Dispatch or Route Assistance. Feed and Viki Videos work the same way.
Because a group with no visible pages left is dropped rather than shown empty, a whole heading can vanish this way. The giveaway is that nobody at your company sees it. To turn a feature on, contact VoiceERP.
Your subscription has lapsed
If a page opens onto a dialog headed "This is a Paid Feature" saying "Your subscription has expired. This feature is only available to paid users," the feature exists for you but billing has stopped. Its Sign Up button takes you to the billing settings, and a Home button sits alongside. On other screens the same dialog appears only when you press a particular button, and you can dismiss it and carry on with the rest of the page.
You may be on a different version, or a different chat role
Chat exists in two versions, and the sidebar entry reads "Chat" either way — so a colleague's screenshot can look nothing like your screen even though you're both in Chat. Which version you get is set for you rather than chosen in the app. Chat also has its own permission level: chat members can message in their channels and start direct messages, but creating channels and personas, and managing members, are reserved for chat admins.
It's still rolling out
Newer areas carry a small chip in the sidebar — "NEW", "Beta", or "Coming soon". Scheduling is the clearest example: companies that don't have it yet still see a Scheduling entry, but it opens a preview page headed "Be one of the first to try it", with a Register interest button that puts your team on the list. Once scheduling is switched on for you, that same entry becomes the real pages.
The quickest way to narrow it down
Ask one colleague whether they can see the page. If nobody at your company can, it's a company feature or a subscription question — talk to VoiceERP. If some can and you can't, it's your page access — talk to your admin, or your root admin for Payroll, Timesheets, Billing and Reporting.