Error 306 when starting delegated harvesting

Hello, ive had a few issues with NCC as of late and when i had to change servers for delegated harvesting, its no longer letting me harvest.

Its saving the server (133.130.111.115) under remote server, but when i click start delegated harvesting, i get unexpected error 306.

Anyone know what this means or how i go about fixing it?

Ive tried other server addresses and i still get the same error.