Hello @mitchelll121 ,
A unique contact is determined by their email address, so uploading the same email address but with different names or physical addresses, will force it to be updated each time.
You may need to do some manual reconstruction of the CSV file outside of our system. I'd recommend having separate columns for Email Address 1, First Name 1, Last Name 1, Email Address 2, First Name 2, and Last Name 2. Then, when you upload the CSV file to your Contacts dashboard, you'll do an initial upload for the 1 fields, then a second upload for the 2 fields. On the page where you assign contact fields, simply exclude the 1 and 2 fields respective to which upload you're doing.
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