Some visits are tracked twice


On one of my websites I have a large discrepancy in visits/sessions between Matomo and GA (40% more visitis in Matomo).

While troubleshooting I discovered that a some of my (and a lot of other’s) visits where registered twice. Same IP, same timestamp, same everything.

I can’t find any patterns regarding traffic source, browser, OS or device explaining this behaviour. It all seems random to me.

The website is a SPA site and uses tag manager for setup. Both me and my dev has checked, and there are no double scripts. I use the same setup on other websites, but has no issues with visits on them.

Can anyone please guide me in how to proceed with this? Kinda stucked right now…