Extra row after filtering

I have a sheet with hundreds of alpha numeric values in column A1, I have to add additional columns and sort/filter to match information quickly. Often, after I sort back to original (sort under condition 1, then 2) I get a new row 1, which is blank. Because of this, I have to redo the sums of certain columns as they disappear. It seems more like a shift of everything than just an additional row, however, I have been unsuccessful solving this issue. Any help is greatly appreciated.

am I the only one this happens to?