According to Dave Meltzer in the latest Wrestling Observer Newsletter, Bobby Lashley had to miss out on building to his match against Aleister Black at WrestleMania due to coronavirus concerns. Lashley was supposed to be on the March 16th episode of RAW to kick off their rivalry, but he had been forced to quarantine after returning from South America.
The reason Lashley was in the country was because he was promoting WWE's visit to the country this May...which has now been postponed to September due to ongoing concerns about the global pandemic.
He did end up taping the WrestleMania match alongside Black earlier this week, so his time in quarantine was likely just a case of being safe rather than sorry. Chances are something was taped for Monday's RAW to explain why the two Superstars are suddenly going head to head at the Show of Shows.
Lashley was last seen on the March 9th episode of RAW, and Lana is back in WWE after production on her movie Cosmic Sin (which also stars Bruce Willis) was put on hold along with other film productions.