I am using out of the box functionality for Lead Conversion through the Convert button on the lead detail page. There are several custom fields on the Lead object which need to be mapped to Opportunity on conversion. The Lead object has 2 different Record Types and opportunity has 4 different Record Types. The custom fields on Lead and Opportunity are identical Text(100), and correctly mapped on the lead mapping.
The problem I face is that some of the custom fields are blank on the Opportunity record even though there is a corresponding value in the converted Lead. I understand that record types play a important role during the lead conversion. I tried using the default record type assigned to the user profile. Still the values on the opportunity are not visible. How can I debug further and discover the root cause?