Sometimes Pulse can get into a strange state where it gets a corrupted thumbnail image, and then the thumbnails requested after that are also corrupted. This issue seems to have been resolved with app updates. The newest app version is v1.13.3 (v1.11.3 for Android). We recommend using the newest app. If you are still having trouble with this issue please check the below solutions or shoot us an email.
Note: Unfortunately this is not the case for the latest releases of iOS (14 and above) and Android (11 and above). We are working to address this issue.
There are a few other reasons that we have found that can result in thumbnails coming back corrupted, or not at all.
Still stuck? Shoot us an email. We're here to help.