Visits Data is not matching when compared in Analytics for AEP Web SDK vs Client Side implementation

We recently implemented AEP Web SDK for our website, following all the necessary steps. However we've noticed a discrepancy in the "Visit" metric when comparing the analytics between AEP Web SDK and Client-side implementation. The difference is approximately 20%. It's important to mention that all other metrics are functioning correctly, with a discrepancy of less than 3-5% for other metrics.