To delete a blocked contact on WhatsApp, follow these steps: Open WhatsApp and go to the Settings menu. Select Account and then Privacy. Scroll down to the Blocked contacts section and tap on it. Find the contact you want to delete from the list of blocked contacts. Swipe left on the contact and tap on the Unblock option. After unblocking the contact, you can now go back to your WhatsApp chat list and delete the contact's chat history by pressing and holding on the chat, then selecting Delete chat.