i can't change tasks order

hi,

i don’t know why but i can’t change the order of download of my tasks ,when i try to drag the task up or down i can’t do it and my cursor is a ‘‘forbidden’’ icon , i tried to add the ‘‘up’’ button to the task bar but i can’t click on it , so i would like to know how i can change the order of download of my tasks and if is a method to lock the position of the task list how i can disable it . i also tried ctrl+up keys but nothing worked , what can i do ? before ,everything worked fine but i don’t know what’s wrong .so if somebody can help me it would be great .im using windows 10 build 10162 x64. thanks

the order that your tasks are sorted has changed. Click on the “name” column until the up button is active,