OLD but so we know what the issue reportedly was:
Adam Schefter of ESPN reports that the league and the NFL Players Association are investigating whether the Titans failed to follow the protocols developed jointly by the NFL and the NFLPA.
“This isn’t a failure of the protocols; it is a failure to follow the protocols,” an unnamed source told Schefter.
The investigation reportedly is focused on outside linebackers coach Shane Bowen. Per the report, Bowen “was exposed to individuals who had been exposed” to the virus. The rules require all personnel to report that they were in the presence of someone who has the virus, or to not report for work if that has occurred.
The probe also is exploring whether the Titans were diligent when it comes to wearing masks in the facility. Frankly, based on the constant images of coaches and sideline personnel failing to properly wear masks when in the presence of TV cameras during games, it should surprise no one to learn that mask irregularities have happened and will happen at most if not all team facilities.
https://profootballtalk.nbcsports.com/2020/10/04/nfl-nflpa-explore-whether-titans-violated-protocols/