Hi Annie,
from async/await standpoint, your code is fine. It should be something like:
await payNow()
await wixData.insert(...)
wixLocation.to("/success")
My guess that there is an issue with Stripe payment code.
Furthermore, I’m not sure about the flow of your site, but inserting paid member from frontend looks like a risky move. This should be safely done in backend code by checking if the payment was actually accepted.