Account Generation failed for new balancing segment

can sombody help me why i am getting this Account generation error.

we use  budgetary control and  encumbrance accounting.

I have created a new balancing segment and creating requsition with the new balancing segment, I get an error account generation failed. contact your system adminstration if necessary.

Workaround :-If i click return , click on view cart and check out, click on edit lines , click on account, make no changes, clcik return, the requistion is created.

Being an encumbrance accounting, the entries are not transferred to GL.  I do not have issue with the existing balancing segment, it is with the new balancing segment.