If you have one of these issues (in any TGX version for the last year, better not beta):

1. Files need to be redownloaded after phone restart / other event. After clicking on a download button, it downloads again (starts from 0%).
2. Files need to be redownloaded after phone restart / other event. After clicking on a download button, it almost immediately finishes downloading (100%).

First, verify that Settings > Data & Storage > Storage Usage > Keep Media is set to Forever.

Then kindly submit report to the testing group:

0. Specify whether you have #1 or #2 issue.
1. Exact steps to reproduce (if you know them). Like following: I download file, do X, then file download state becomes invalid.
2. If you don't know steps to reproduce, check & confirm if problem reproduces after changing time zone in system settings & restarting the phone.
3. Kind of affected files (any files, only audios, only documents, etc)
4. Include Full device model & Android & TGX version, like for any other report.

This is a very old issue that happens on a small percentage of devices and I'm unable to reproduce it. Technical reasons of why this happens are yet unknown. I would be glad if this issue will become resolved, since it sounds painful.