Display/Edit mode in IR - SCV

Hi all GURUS,

I'm new to PI.

I cannot edit any vlues in a particular Software Component Version & its name spaces & values (DT , MT, MM, SI,OM). This was previousely working fine & I wanted to change the DT of particlar name space & it doesnt allow me to do. Only I can do is viewing ."Software Component Version Cannot be changes" appears only on that SCV. Other SCV's are working fine. How do I enable this option ?

Thank you all in advance