data-mm-id=”_sutiu8g20″>The Buffalo Bills began their mandatory minicamp on Tuesday with glaring absence: star receiver Stefon Diggs. While Diggs not being there was a huge topic of conversation, no one is saying what the problem is. It apparently has nothing to do with money or a new contract, so we have no idea what it could be. Bills head coach Sean McDermott said he was "very concerned" that Diggs wasn't there on Tuesday:Stefon Diggs is NOT here at #Bills mandatory minicamp. Sean McDermott says he’s ‘very concerned’ but would not go anymore into his absence. #BillsMafia @BuffaloPlus— Dan Fetes (@danfetes) June 13, 2023ESPN's Josina Anderson is reporting that Diggs' absence isn't about money:2/2 I’m told the nature of the private talks is “n…