O WhatsApp on mobile phones Android it may fail to identify the contacts and when this occurs, the user sees only the number in the conversation list - not the name or nickname, as it should for the contacts saved in the smartphone's calendar.
If you have faced or are experiencing this problem, please know that the solution is simple:
Step 1. Open WhatsApp and tap on the menu icon in the upper right corner of the screen. Then select "Settings".
Step 2. Access the "Contacts" settings and uncheck the option "See all contacts".
Step 3. A message will inform you that the contacts have been updated. Click "OK". After that step, you can activate the option again.
This way, you can force your WhatsApp contact list to be updated to resolve identification issues.
In good time this article came! Not even a day ago I was struggling with a bore related to contacts on Whatsapp! Good!