Crawler gets a 403 - Forbidden

hello,

for me the crawler isn't working as expected, according to the logs it always get a 403 when accessing /boost-crawler.
/admin/reports/status tells me to "Menu item for crawler is not there. You need to "Clear cached data" at the bottom of the performance page" which has no effect whatsoever.

Any suggestions on what i could do next to figure out why the crawler is getting a 403?

thanks in advance