Valuated stock becomes negative Message No:M7314

Dear All,

For a definite worldly benignant lawsuit wants to make PO with relationship duty K. Initially it was non valuated material. So we prime the quantity and worth update for that worldly type.

 material benignant was defined arsenic non-valuated initially and was past turned into valuated portion we already had stock

Now preservation created for that worldly with mvt benignant 201.When the idiosyncratic tried to bash PGI (MB1A) w.r.t preservation for that aforesaid worldly it is showing mistake msg arsenic "Valuated banal becomes antagonistic Message No:M7314".

Note:

Quantity is disposable successful worldly maestro besides shows successful MMBE.

Please archer maine however to rectify this error. Is this mistake owed to alteration of worldly from non valuated to valuate stock?