Podcast Thumbnail Request Rejected

Contribution ID#s 250411-190455-558802, 250408-044829-396602 Hello, I am trying to get my new artwork used as the thumbnail for my podcast, and the old artwork removed. I have made several requests and each has been rejected as not conforming to image guidelines or image formatting. Per IMDB Help section, " IMDb supports JPEG and PNG images. Images must be no smaller than 50 KB and no larger than 25 MB. Both the image height and width must be between 500 and 8000 pixels. Based on the dimensions, IMDb may crop the image as necessary. For Film and TV posters, to minimize cropping, we recommend a vertical alignment (i.e. portrait orientation) with an aspect ratio of 1:0.675. For Podcast covers, to prevent cropping, we recommend a square (1:1) aspect ratio as is the industry standard for audio titles. We recommend always providing the highest quality image available." The image I am requesting be used for the thumbnail is 1500x1500 and 3 megabytes. I cannot get an explanation as to why my new image is being rejected, as it conforms to IMDB specs and has already been uploaded to the show page. Please help. Thanks...JM