You can set how strict you want our software to be when merging or detecting duplicate customer records as they come in. The fewer fields you use to detect a duplicate, the more likely we will find and assign the incoming customer information to a record already in your database. Be careful to select unique fields if you are not selecting many parameters for us to check. For instance, only choosing name would not likely be a good way to set it up, but only choosing email address may work very well for you.
You may also tell us how to merge the information coming in when we detect a duplicate record. We can keep all existing information when there are differences or overwrite the existing information with the new information. In either case if the existing customer record is missing information, we will fill it in with the new information coming in.