It is conceivable that the new update will automatically change or override your current network settings, causing network issues. This could be the primary cause of online programs such as the App Store malfunction or acting strangely. To rule this out, try changing your network settings. This will restore your iPhone's default or original network settings and options. Then, before the problem occurs, you can configure individual network options based on your prior preferences. This is how it's done:

1. From the Home screen, select Settings.
2. Select General.
3. Scroll down to Reset and tap it.
4. Choose Reset network settings from the list of alternatives.
5. To proceed, enter your device's passcode if prompted.
6. Tap to confirm that the network settings have been reset.