In the NFL opponents are going to score. Teams are going to have turnovers. Not every turnover and not every opponent score is a "bad" play, in the sense it is out of the ordinary.
By this standard, the Bills have had three bad plays this season. The TD return. Bass's missed FG, Bass's missed XP. Thats it, all the other plays could be argued to be good plays by the opponent.
This is a truly remarkable run of three games.
PS. I am old enough to remember the plan to build the team around a highly paid Ryan Fitzpatrick not that many eons ago, after a 3 game win streak.