My Leads and Accounts/Contacts have custom fields, but when I go to convert the lead some of the data does not map properly. How can I map the fields so I can avoid duplicate data entry.
If the fields have the same field name, the data will get copied during the lead conversion. (Note that the match is on field name, not label). See How to Copy Values from Lead Form to Convert Lead Form for a more detailed response.
If the field names are not the same, it is possible to create a code customization so that the data will copy. This post Lead Conversion stop one field from copying to Accounts should point you in the right starting direction.
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