You can find below the steps to Delete and Reinstall WhatsApp on iPhone, in case WhatsApp is not working properly or due to any other reason.
Reinstall WhatsApp on iPhone
In order to Reinstall WhatsApp on iPhone, you will have to remove the current version of WhatsApp as installed on your iPhone.
Before you do this, it is important that you make a backup your WhatsApp Account to iCloud Drive, so that you can make use of this Backup to restore WhatsApp.
After this, you can go ahead with the steps to delete WhatsApp from your iPhone and Reinstall it back on your device, using the iCloud Backup.
Step 1. Backup WhatsApp to iCloud Drive
As mentioned above, the first step is to Backup all your WhatsApp Messages to iCloud Drive.
1. Open WhatsApp > tap on Settings tab in bottom menu.
2. From WhatsApp Settings screen, go to Chats > Chat Backup.
3. On the next screen, select Back Up Now option to start the process of backing up your WhatsApp Messages to iCloud Drive.
Note: By default, the option to backup WhatsApp Videos is disabled on iPhone, but you can enable this option, if you have enough storage space in your iCloud Account.
Step 2. Delete WhatsApp from iPhone
After making a backup of WhatsApp Messages and Photos to iCloud Drive, you can safely delete the current version of WhatsApp as installed on your iPhone.
1. Tap and Hold on the WhatsApp icon located and select the Delete App option in the menu that appears.
2. On the confirmation pop-up, tap on the Delete option to confirm.
Step #3. Download & Reinstall WhatsApp on iPhone
Follow the steps below to download and reinstall the latest version of WhatsApp back on your device.
1. Open the App Store on your iPhone and Download WhatsApp on your device.
2. Once the download is complete, Open WhatsApp and follow the instructions to provide WhatsApp with access to Contacts and agree to its Terms of Use.
3. On the next screen, select Country, enter your Phone Number and tap on Done.
4. On the next screen, select Restore Chat History option.
Patiently wait for the Restore process to be completed, after which you will have fully functional WhatsApp Account.