It might work better to leverage the Data Cleanup App.

You can identify WHY people are duplicating records.

• accident?
• misunderstanding?
• lack of tracking?

You can then address the issues. If you block people from duplicating, it might frustrate them when they legitimately need to duplicate things in order to do their jobs.

Legitimate reasons for duplicating records:

• to save time when needing to create some thing very similar to something that already exists (like a Customer ordering the same things they did last time)
• to maintain a history of prior records (a customer requires several adjustments to their quotations before deciding on a final order)
• to minimize errors (a payroll journal entry is the same each month apart from the amounts)
• to correct errors (it might be faster and more accurate to duplicate a record and archive the original)
• to address mistakes (if an inventory transfer is accidentally cancelled, Users can duplicate it and continue working)
  
  

https://www.odoo.com/documentation/17.0/applications/productivity/data_cleaning.html

Thanks Vishnu, unfortunately most of the duplicates are in products.

example to remove duplicates of contacts you can Insert the following Pythoncode

partners = env['res.partner'].search([])

seen = set()

duplicates = []

for partner in partners:

    identifier = (partner.name, partner.email)  # Adjust this to your duplication criteria

    if identifier in seen:

        duplicates.append(partner.id)

    else:

        seen.add(identifier)

if duplicates:

    env['res.partner'].browse(duplicates).unlink()