Media and Javascript/CSS not included in export because of 404 error

Hi,

i have a strange error when running an export. No media/javascript/css files are included in the export:

The export log is showing the following

Crawling https:/domain.com/wp-content/cache/autoptimize/css/autoptimize_snippet_1850419e4cfbe4e444263f8e2ee0328b.css
BAD RESPONSE STATUS (404): https:/domain.com/wp-content/cache/autoptimize/css/autoptimize_snippet_1850419e4cfbe4e444263f8e2ee0328b.css
Memory allocated by crawl script: 2048
Exclusion rules wp-json
Crawling https:/domain.com/wp-content/cache/autoptimize/css/autoptimize_snippet_1c43cb8f91d07e97aa58658c8a1f4497.css
BAD RESPONSE STATUS (404): https:/domain.com/wp-content/cache/autoptimize/css/autoptimize_snippet_1c43cb8f91d07e97aa58658c8a1f4497.css
Memory allocated by crawl script: 2048
Exclusion rules wp-json
Crawling https:/domain.com/wp-content/cache/autoptimize/css/autoptimize_snippet_29870e94c74d4506a6b6bff969948945.css
BAD RESPONSE STATUS (404): https:/domain.com/wp-content/cache/autoptimize/css/autoptimize_snippet_29870e94c74d4506a6b6bff969948945.css
Memory allocated by crawl script: 2048
Exclusion rules wp-json
Crawling https:/domain.com/wp-content/cache/autoptimize/css/autoptimize_snippet_9eeddc51b0b4a2580a959042d50f826e.css
BAD RESPONSE STATUS (404): https:/domain.com/wp-content/cache/autoptimize/css/autoptimize_snippet_9eeddc51b0b4a2580a959042d50f826e.css
Memory allocated by crawl script: 2048

It is really strange, because if I open the URLs in my browser, all of the files exist.
I already tried to disable the minify plugin, tried it without an minify plugin, but it is always the same. The files in the wp-content folder can not be included because of the 404.

I also tried to do the export again because I thought maybe it regenerates the cache files on each export. But when I check the source code of the page, the cache files stay the same with each export. I can perfectly access the files in the browser but the crawler gets a 404 response.