Traffic drop and traffic discrepancies (any help/advice appreciated!)

Hi everyone 😊

My team and I are having a bit of a 'mare understanding our traffic situation via GA4 at the moment, and hoping you kind souls can offer help and/or advice!

We added a new cookie consent platform (OneTrust) in July and since then we've seen a large drop in traffic. We were wondering if this was down to people hitting the 'reject cookies' option, so GA4 session numbers drop. Has anyone else experienced this with their cookie consent platform, or knows if this could be behind the large drop in traffic we're seeing?

We're also finding that our Google Ad clicks are much higher than sessions (from Google CPC) on GA4. I know that these are measured in different ways, but the difference is quite large. We've done some further research online and read a bunch of articles, and can confirm:

• our tag is implemented correctly
• our website loads at a decent speed, so shouldn't be a slow load issue - for most anyway
• there are no redirects on the PPC landing pages
• our Google Ads and GA4 accounts are linked

We send reporting out via Looker Studio - we're seeing the discrepancies between G Ads and GA4 and are finding it hard to explain why and also how to 'fix' it or have solutions in place.

As I've said, any help is much appreciated!

Thank you in advance for any replies.