Linelength in snaphu export and what to do about it

I have SNAP 6.0. When I try to use snaphu in Linux Ubuntu with a wrappedphase Sentinel 1ifg file it gives me an error about line length needing to be a positive integer. What does this really mean? Is it talking about the width or the height of my source file? My file is 21186 x 12225. Does it mean that I need to subset the source to be positive integers in both X and Y directions? Or something else?