Well, it’s what it says it is: too many redirects. I can’t tell what’s causing that. If it only happens with Relevanssi, try disabling the custom excerpts from Relevanssi. Perhaps you have something in your excerpts that causes the redirect?
I disable the “Custom excerpts/snippets > Create custom search result snippets”, but still get the same result.
Is there any way to debug the issue? I see there is a “debug” tab.
The error is caused by Yoast SEO option:
Internal site search cleanup > Redirect pretty URLs to ‘raw’ formats
After disabling this option, then everything is OK.