That issue can be a hardware issue and it can be a sign that the firmware and T2 chip needs to be revived or restored. 

 - [Revive or restore Mac firmware in Apple Configurator 2][1]

I would back up your data and test well so you know the backup is complete and good before you either seek repair or attempt to fix this. 

To fix this, we use another Mac and [Apple Configurator 2][2] to reload the non Mac firmware using an iOS-like DFU process described above. Your data will not be recoverable if service decides this is needed or swaps parts. Same if you attempt to revive things - this makes all data unrecoverable if it fails or if it succeeds. You should be prepared to reinstall macOS and then load your data, Apps, settings from backup if you start this test, but we have seen it resolve this specific glitch. 

  [1]: https://support.apple.com/en-lamr/guide/apple-configurator-2/apdebea5be51/mac
  [2]: https://apps.apple.com/us/app/apple-configurator-2/id1037126344?mt=12