One of the most disappointing seats on a Boeing 737 is central to a lawsuit filed in a federal court in San Francisco this week. A San Francisco man joined the class action suit against United Airlines Tuesday, alleging the airline charged him extra for a window seat that was actually next to a wall.

Delta Air Lines and United Airlines were sued on Tuesday by passengers who claimed they paid extra money to sit in “window” seats, only to find themselves placed in seats next to a blank wall.

United Airlines and Delta Air Lines are facing class action lawsuits from passengers who say they paid extra for window seats only to discover there were no windows beside them.