VTP configuration checklist

To ensure VTP functions, make sure these items are configured correctly:

  1. Make sure the correct switches are configured as servers and client.
  2. Make sure that the domain is the same.
  3. Make sure that the VTP version being used is the same.
  4. Make sure that the password being used is correct on all devices.

https://networklessons.com/switching/introduction-to-vtp-vlan-trunking-protocol