Help for using the Get Data > EBI-SRA tool: https://wiki.galaxyproject.org/Support#Get_Data:__EBI-SRA
Make sure that you are using the links that send data to Galaxy. Please note that sometimes the EBI-SRA server is busy and re-running a tool query will often correct an error. Also, the website has a banner stating that they are undergoing maintenance. I am not sure if that is a factor, but you could check with them directly. A test load at Galaxy Main (http://usegalaxy.org) just now was successful.
If you cannot resolve the problem and are working at http://usegalaxy.org - or can reproduce the problem there, please send in a bug report and we can help further. Please leave all datasets and job outputs, even errors, undeleted. This is how: https://wiki.galaxyproject.org/Support#Reporting_tool_errors
Thanks, Jen, Galaxy team