I drove a planned route 1300 meters in altitude yesterday. The Edge indicated over 2000 meters of altitude beforehand. Climbpro showed both gradients and descents as gradients. Is there a solution for this.
The course was downloaded and directly send to Edge as a GPX file. The file was not created by me. But from a hotel that specializes in road bike tours.
It looks like bad elevation data in the file


Yes, there is. You can read it in my post in the 1030 section:
Please scroll down to the last part. You have to convert your GPX file to TCX. You can do so by loading it in BaseCamp, save as TCX, then adjust the values with notepad or another editor. For the rest you can follow the way described in the post.
Good luck!