Hi there! Sorry to hear you're having trouble.
Our crawl error guide is a great place to start to find more information. You might consider running a Crawl Test on the site to validate the error, as it could possibly have been a temporary issue. If you're still seeing the error crop up, it probably warrants additional investigation.
Usually a 5XX error means an issue on your server, so you might wish to inquire with your web dev about the cause. If you're still not sure what to do, the Q&A forum is generally a great place to look for ideas in resolving some of these issues. Here are some articles that might help: