Page with tabs not show all tabs if have a custom navbar

Questions
1

Hello,
i have a page with seven tabs.
when display a page the tabs function right. When go to home and return to tabs page can’t view the tabs. I click on second or another tab the cursor go to tab but the layout not change.
I have a custom navbar.
If change the custom navbar with standard navbar the problem is solved.
Why ?

Custom navbar

 <f7-navbar>
        <f7-nav-left>
          <f7-link href="/">
            <f7-icon md="material:arrow_left" class="icon f7-icons"></f7-icon>
          </f7-link>
        </f7-nav-left>
        <f7-nav-title>New card</f7-nav-title>
        - {{info_sub_area}} &nbsp;&nbsp;&nbsp; <p> <f7-checkbox :checked="check_complete" @change="check_complete= $event.target.checked"></f7-checkbox> Date ok</p>
        <f7-nav-right class="margin-right">
          <button class="button button-fill button-raised" type="submit"><f7-icon md="material:save">
          </f7-icon> Save</button>

        </f7-nav-right>
      </f7-navbar>

Classic navbar

<f7-navbar title="New card" back-link="Back"></f7-navbar>

The problem persist if i have a Appbar

2

Didn’t get anything, what is the issue? Would be good to see live example or more relevant code examples