Hi there! I see you're having trouble opening the Trade Republic app on your iPhone. Let's figure this out together.

To start, could you tell me if you see any error messages when you try to open the app? Also, have you tried anything so far to fix the issue? This info will help me guide you better.

In the meantime, here's a step-by-step approach that usually helps fix app launch issues on iOS:

1. Close the app completely: Double-press your home button or swipe up from the bottom (depending on your iPhone model) to open the app switcher, then swipe the Trade Republic app off the screen to close it.

2. Restart your iPhone: Press and hold the side button and either volume button until the power off slider appears. Slide to power off, wait a few seconds, then turn it back on.

3. Check for app updates: Open the App Store, tap your profile icon at the top, then scroll down to see if Trade Republic has an update available and install it.

4. Reinstall the app: Sometimes uninstalling and reinstalling the app clears corrupted files. Press and hold the app icon until it wiggles, tap the 'X' to delete it, then reinstall it from the App Store.

5. Check your iOS version: Since you mentioned iOS 18.6, that's good because the latest updates often fix app compatibility issues.

If after trying these steps the app still won’t open, let me know, and we can dig deeper into account issues, network settings, or check for any outages.

Does any of this make sense? Would you like me to walk you through any of these steps?