Help! I have lost all chat history in WhatsApp!!!!

Hi

I just upgraded my iPhone (as I have done many times in the past). The only difference this time was that I had moved from Whatsapp to Whatsapp business. After the Phone upgrade WhatsApp Business asked me for the encryption password for my chat back up - I had never enabled this in WhatApp in the past. So after a few tries, I contacted WhatsApp Support, I got a standard email that they will get in touch with me. In the mean while (after about half a day) I opened WhasApp on my Phone and it asked me if I wanted to move back from WhatsApp Business, and I said yes. I then got WhatsApp open but while all the groups and contacts were there the chat history was only from today (all the previous messages have disappeared). I have tried contacting WhatsApp multiple times but no response (other than the standard response). I need to know if there is any way for me to access my chat history. . I am desperately looking for a solution (have tried many software tools like UltData (Tenorshare) / iMyFone ChatsBack etc. no help. They all only show me the chat from today onwards. Please please please help!!!​​​​​​​
Windows / Chrome 114.0.0.0