The Active, Inactive and Waiting statuses indicate different things on the different pages.
On your Staking Dashboard page:
Inactive = your stake is not actively supporting this Validator during the current Era.
Active and earning = your stake is actively supporting this Validator during the current Era and earning rewards.
Waiting = This Validator is not in the Active Validator Set for the current Era.
On the Validator Selection or Validator Information pages:
Active = This Validator is operational and active in the current Era; you can Nominate your stake to this Validator and earn rewards if your stake actively supports this Validator during an Era
Waiting = This Validator is operational but not part of the active Validator set producing and validating blocks in the current Era. You can nominate your stake to this Validator, but your stake will not actively support this Validator until they are elected as part of the active Validator set for an Era.
Inactive = This Validator is currently not operational, so it is unavailable for election to produce and validate blocks on the network. You can nominate your stake to this Validator, but your stake will not actively support this Validator until it is operational and available for election into the active Validator set for an Era.
For more information, see the Staking Protocol section of The Root Network Docs Hub.