Hi there! I understand you're having trouble updating the MyBSWHealth app on your iPhone with iOS 18.4. Let's get this sorted out together.

First, can you tell me if you’re seeing any error messages when you try to update? Also, is your iPhone connected to Wi-Fi or cellular data when trying to update the app?

Meanwhile, here are some steps we can try to troubleshoot the app update issue:

1. Check Your Internet Connection: Make sure your iPhone is connected to a stable Wi-Fi network or cellular data, as app updates require internet.

2. Restart Your iPhone: Sometimes a quick restart resolves temporary glitches. Press and hold the side button along with either volume button, then slide to power off. Turn it back on after a minute.

3. Check Available Storage: Ensure your iPhone has enough free space for the update. Go to Settings > General > iPhone Storage to see if your available space is sufficient.

4. Update Apps Manually: Open the App Store, tap your profile icon at the top right, then scroll to find MyBSWHealth under available updates. Tap "Update" next to it.

5. Sign Out and Back Into App Store: Sometimes, signing out of your Apple ID and back in can clear update hiccups:
- Go to Settings > [your name] > Scroll down and tap Sign Out.
- Sign back in after a moment.
- Open the App Store and try updating again.

6. Delete and Reinstall the App: If updating still won’t work, you can uninstall MyBSWHealth and reinstall it from the App Store. This usually installs the latest version.

Please try these out and share what happens or any errors you encounter. That will help me guide you further.

Are you currently seeing any specific error during the update process?