That image is the “placeholder” for Lucid’s widget. If you see that for more than a few seconds, that means the widget is not able to successfully get its data from the app itself.
Sometimes launching the app will kick it into gear. Other times, it stays that way for a while. If your other widgets are working, and a restart doesn’t help, it could be something else Lucid didn’t anticipate happening in your phone.
It’s possible the widget needs to communicate with a server. So if you are in Airplane Mode or otherwise not connected to the internet for a while, things like this can happen. Because widgets aren’t constantly updated (that would destroy your battery life) once a widget gets into a broken state it can stay that way for quite a while.
I’d report it to Lucid and hope it gets resolved in the future. I’ve found troublesome widgets will just start working on their own again occasionally. But they need to be told these types of issues are happening.