File stuck uploading from iphone to OneDrive - how quit uploading, what is wrong?

Hi!

Yesterday I started uploading a file from my iphone 5s, latest iOS version, to my OneDrive account. This has worked excellently in the past (except that it doesn't accept files with foreign letters).

The file still keeps uploading, stuck at 5243 kB out of 5798 kB. I have left and returned to the app on the iphone a few times, it keeps being at this stage, and uploading, as it seems perpetually.

The file is not visible on the OneDrive account, when accessed from my computer.

Questions:

1. How do I exit the uploading on the iphone?

2. What did I do wrong? How should I do?

Thanks a lot in advance for any suggestions!

BR