Connection Problems to the Server

Hi Guys,

hope its the correct Category for my Question. Excause my poor English.
I use the App “Files” on my IOS Device. Nextcloud is as a Location activated and i can upload in this App Files to my nextcloud Server.
If i want to Download a File i get an Error that the Device couldnt connect to the Server.

What maybe is my Fault to solve this Problem? Uploads are Working, Donloads couldnt.