I purchased a Nissan filter at the dealer about two months ago and noticed that there is a section around the inner tube on the bottom of the filter that is missing glue and the pleats of the media can be seen through this groove. I visited the dealer again yesterday and looked inside another filter (same filter number) and it has the same issue. So I guess maybe this is normal for these filters or at least this batch. I have never seen that problem in any other filter brand. Could this missing glue cause any problems or is it irrelevant for the proper functioning of this filter?