Email sign ups so slow = customer drop off/complaints

I'm new and looking for a home for my new community. I'm down to the last two having trailed a few (once I build it I don't want to move it so I'm taking care to find the right one). The massive sticking point for me is the sign-up process - you sign up and wait for the email with the link and then it's crickets for up to 10 minutes. I just thought it hadn't worked tbh. And when the email does eventually arrive there's just 1 hour and then the link is no longer live. This would be fine if the email arrived immediately so that the process is seamless, but others on the forum have stated that they see a huge potential customer drop off as a result of this. Such a shame as everything else about Heartbeat ticks all my boxes.