Here are some Python based tools to help find records that refer to the same customers to support your record DeDuplicating initiatives.
Dedupe (pip install dedupe) https://pypi.org/project/dedupe/
pandas-dedupe (pip install pandas-dedupe) https://pypi.org/project/pandas-dedupe/
Basics of Entity Resolution with Python and Dedupe https://medium.com/district-data-labs/basics-of-entity-resolution-with-python-and-dedupe-bc87440b64d4