records in sitecore experience analytics are 10% fewer than those in google analytics

Hi guys

I'm working on one sitecore 9.01 project, and it has both experience analytics and google analytics, but the number of records are different.

Google analytics is monitoring how many times of the submit button been toggled, and sitecore analytics inside backend, registering sitecore goal.

But in our aws s3, google analytics is more accurate and closer to the actual forms we receive.

I put two screenshots of record of submitting forms in one day, one is from google and the other is from sitecore analytics. In google analytics, we got 550 records, in siteocre, we got 496. and in aws s3, we got 577 forms. I also checked previous records, sitecore analytics always has 10% less than the actual records. 


Could you guys know the reasons and how to fix it?