Need someone with experience in fixing google console (Sitemap) 403 http error

So right now i can't submit my sitemap, its auto generated sitemap, tried manually create the sitemap with another website tools but still can't submit, it keep saying General HTTP error: HTTP 403 error (Forbidden). Also on the Access denied list, all links show this status : Googlebot couldn't crawl your URL because your server either requires authentication to access the page, or it is blocking Googlebot from accessing your site. My google robot txt is using allow all, so it shouldn't be an issue, my main website is able to index, just my two new websites is not able to ( one of the new websites is few months old, still can't index ). So there must be some configuration wrong on the folders or htaccess or something, i am using cpanel, as well a bootstrap site ( not wordpress ). If you have solve this before, do bid, i might pay very well if you can fix two my sites sitemap issues, one of them have been same error for months. Prefer someone who knows about google search console and work on cpanel folders, htaccess, sitemaps before. Will re-hire again for new website error if you can fix this well. Thanks. Thanks.