This is very normal, and has to do with how Bitcoin's consensus mechanism (PoW) functions.

The best explainer I've found is now only available on web archive, I hope this gives you a better understanding of how Bitcoin Mining works and why Blocks can arrive 1 second later or 60 minutes later. Here's the link: https://web.archive.org/web/20221101044402/https://minerdaily.com/2021/12/31/how-are-bitcoins-difficulty-and-hash-rate-calculated/