Unfortunately, it's impossible to recover deleted WhatsApp messages on iPhone without a backup, as you can only save your WhatsApp chats to iCloud.
How to See Deleted WhatsApp Messages on iPhone. If you have backed up your WhatsApp messages to iCloud, you can see the deleted WhatsApp message by restoring the backup.
Once the messages get deleted, they are not visible on WhatsApp, but you can see them on the ”Get Deleted Messages” app.
You can restore messages you deleted for up to 30 days. , then do one of the following: Tap Edit, then tap Show Recently Deleted. Tap Filters, then tap Recently Deleted.
All of your deleted text messages can be found in the Messages app. To find your trashed messages, open Messages and tap the Filters option in the top left of your text threads. Here you can filter your text messages by known senders, unread messages and more.
Make sure your messages are backed up to iCloud.
Tap your name at the top to open your Apple ID details. Tap iCloud. Look for "Messages" in the list of backed-up items. If its corresponding switch is on (green), your messages are backed up to iCloud and you can use this method to restore deleted texts.
When you delete a piece of data from your device — a photo, video, text or document — it doesn't vanish. Instead, your device labels that space as available to be overwritten by new information.
Normally your deleted text messages will be kept for 30 days. After 30 days, they will be permanently deleted and you will have difficulty restoring them to your phone.
Clearing or deleting your messages on your devices doesn't mean the data is permanently gone, it's just been filed away differently.
However, just because you erase texts on Apple and Android products doesn't mean they're gone for good, according to an expert on the Apple Support Community and Business Insider. They will be hidden, but they may still be saved in system data or elsewhere with your cellphone carrier.