Hi there! I understand that you're facing an issue with your SI Smartphone Printer app where not all your photos are showing, making it difficult for you to select and print what you'd like. I'd like to help you with that.

First, let's go through a few steps to troubleshoot this together:

1. Check App Permissions: Ensure that the app has the necessary permissions to access your photos. You can do this by going to Settings > Privacy > Photos and making sure the SI Smartphone Printer app is set to 'Read and Write'.

2. Refresh the App: Sometimes, simply closing the app completely and reopening it can help. Try doing that to see if the photos appear.

3. Reconnect the Printer: Verify that your iPhone is connected correctly to your printer. Go to Settings > Wi-Fi, and check if you are connected to the correct printer network (it should display a name like "Direct-SI-XXXX").

4. Restart Your iPhone: A simple restart can refresh various services. Just hold down the power button and slide to power off, then turn it back on.

5. Clear App Cache: Reinstalling the app can also sometimes resolve these types of issues. You might try deleting the app and then reinstalling it from the App Store.

If you’ve already tried any of these steps, let me know, and we can dive deeper into other solutions or adjustments.

Are you able to try any of these suggestions, or do you need more assistance with something specific?