Visitor ID Clarification on email campaign in Adobe Analytics

Silver Contributor
Silver Contributor Jayakrishnaa

Generally, we used to get visitor ID report from Adobe Data warehouse for the email campaign. However, recently we have noticed some different scenarios on the reports. Looks like, the login ID will be geneated automatically once they click any button or link from the email and they will reach to the site accordingly. In the report, we have seen two visitor ID’s for the single ID login. so, we are just wondering how come this happened? We understand that cookie’s will be used to identify the visitor ID. What are other possible ways that the cookie with get expire and another visitor ID will get generated on the same login apart from below?

Clearing cache, using incognito mode, in another device and cookie get expire.. Please assist us to find more solution for the request.