Haha 🤣 Is it possible you're misreading the notifications? I thought the same was happening to me before until I realized how primal shows zap notifications. Each time a new zap comes in, you get a notification showing who the new zap is from along with the cumulative total of zaps on that post. But if you want to see what their individual zap was, then you have to go into the wallet and find it in the transaction list. Like this example, I got a zap from user nybe and the notification shows a total of 1.1k sats, but his individual zap was 21 sats. The 1.1k was the cumulative total on the post. 
Discussion
That’s some of them
Okay so I’m reading it wrong? 😂😂
Yea, but it's confusing the way they word the notification. The " for a total of 640 sats" is the cumulative total on that note, not the amount of each of those individual zaps. To see the individual amount each of them sent you, you have to look in the wallet transaction list. I wonder if nostr:npub12vkcxr0luzwp8e673v29eqjhrr7p9vqq8asav85swaepclllj09sylpugg might be able to improve that notification wording so it's clearer. nostr:npub16c0nh3dnadzqpm76uctf5hqhe2lny344zsmpm6feee9p5rdxaa9q586nvr