Google analytics data not matching Power BI

Hi, I know this has been a topic on several discussions before, but I can't find a solution that works. I'm new to Power BI and I've connected our company GA account with Power BI. However, when I try to display the data, it doesn't match - this is particularly the case with users/new users/returning users/sessions etc. I'm not particuarly technical, so I was wondering if there's a solution that isn't API based. If I need to edit the code, could someone please talk me through it step by step?

Thanks.