temporarily unable

hello,
I got a problem with my server lately after I update direct admin version 1.26.4 to 1.26.6 keept geting this messagess
"The server is temporarily unable to service your request due to maintenance downtime or capacity problems. Please try again later." it only happend to download files everything else still working fine I try to contact my host provider but for week but not heard from them. please show me how to fixing it.
thanks

that's not an error that DA would generate ... this definately needs to be resolved with your provider.