Change of format from 6000 x 4000 into 4000 x 4000 during importing

During uploading pictures from my Canon EOS 80D to my desktop (i tried to upload a batcht instead of picture by picture what i normally do) the format has changed when i open it in Elements 2020.

Original size is 6000 x 4000 but in Elements it opens at 4000 x 4000. In Canon Digital Photo Professional 4, you see a white frame of 4000 x 4000 in the picture. Also i see this square format now on my camera display.

I do not know whwt happened, but my SD card is now also changed.

Can somebody please advise me what to do.