Data loss during conversion

I have multiple leads that I need to convert and associate with one account. Let's say I have fields A and B filled in with different values on each lead, and this data is supposed to move to fields C and D for the new account. Zoho will only keep the data in these fields from the first lead that is converted, and will not update the values nor store them from what I can see. The lost data is not in the recycle bin area either. Is this stored anywhere in the CRM?