How would you connect with the buyer

There are some very smart salespeople on this sub so maybe some of you can help. I recently started a job as an account manager at a start up that got acquired. Mid market and enterprise HR sales. Pre-acquisition they weren't very connected with their executive buyers and tended to renew contracts with business users. This meant very little expansion on renewals, which is something I want to change.

I'm having an incredibly hard time connecting with buyers on existing accounts at this job, I think possibly because they're used to us as a supplier just dealing with the business users, and also because executive relationships haven't always been nurtured in the past. Has anyone else experienced this or have any tips? It's rough setting up calls with buyers only for them to send a business user in their stead, and making it extremely difficult to push through expansion. I'm having some traction getting my sales director to reach out, but would love not having to do that on every single account. Advice is appreciated!