I am sure I can help you with your problem!
To restore WhatsApp message, you just need Android WhatsApp message recovery, or iPhone WhatsApp message recovery.
This two software, you can choose the right according to your own mobile phone types, they are very powerful software, not only can help you restore the WhatsApp message, can help restore your photos, video, audio, music, SMS, contacts, call records and so on,
I hope my reply will help you!
Detailed method:
How to Recover WhatsApp Chat History from iPhone
How to Recover Lost or Deleted WhatsApp Chat History from Android