There is currently a cell phone outage that is intermittently affecting carriers. This can affect getting text messages from Duo for multi-factor authentication.
The news article is linked below.
https://www.kark.com/news/national-news/att-customers-report-significant-outage/
If you have issues getting your Duo prompts, please contact Campus Support at 479.968.0646 or campussupport@atu.edu.