Error "(429) Too Many Requests" when trying to download only certain chapters

[Tombstone]

Hello,

I've recently discovered "Kemono.su" and wanted to download the latest chapters posted by the bookmarked artists.
The "check for new chapters" function works correctly and tells me that "x" chapters are available,
I can add them to the download list but from then on it's impossible to download the latest chapters indicated in brackets.

Has anyone ever had this problem or knows of a solution?