Performance issues like the one you've described are often resolved by uninstalling and reinstalling the application on your phone, and then logging back in again. If that doesn't help, comment below with the following information:
- The URL of the document so that I can take a look.
- A screenshot of the issue and any error messages that you are provided.
- The type of device, operating system version, and version of the Lucidchart app that you are working from.
Note: apologies for the delayed response here. Our forum host experienced a bug that impeded our ability to respond publicly. However, we wanted to ensure the resolution provided in our 1:1 email support with you was provided here in order to assist other Community members who had similar questions.