characterstics are not available from Query designer formula

Dear Experts,

I have a requirement where in forumla from query desinger has to be modified with new characterstic filed.

when I tried finding Characterstics from "Available operands" but i could able to see Keyfigures and Formula variables only. Characterstics are available.

Following is the requirement with example.

existing formula structure

A= B+C

now characterstic "B" has to replace with characterstic "D".

hence new formula should be as below;

A = D+C.

Note: Query has designed on infocube

Could you please guide me how to proceed further.

Thanks in advance!

Regards,

Mannu.