A. 1. Restart the app and your iPhone to refresh the performance. 2. Clear the app cache by going to Settings > General > iPhone Storage, selecting the Shining Mask app, and choosing 'Offload App'. Then reinstall it.
B. 1. Ensure that your iPhone's operating system is up to date, as updates can improve app performance. 2. Limit background apps running while using the Shining Mask app to free up resources.