IMA11: internal error There is no variant control

Hello,

We have an issue in the appropriation request transaction IMA11 (Investment Management)

This happens when I modify an appropriation request with more than one variant.

When I try to modify any cost (both investment and overhead cost) under the plan values tab of one of the variants, I receive the error message: "Contact your system specialist - internal error. There is no variant control. Message no. AO042"

I tried in debug mode to see where the problem happens, but cannot find a clue.

Please help me,

François