Strange errors come during change SourceExpr value in NAV report designer...

Our colleague raised problem: why he receives strange error during report compile, after he changed SourceExpr value for some control in report designer in NAV 2009. Error message was: Error while validating RDL content: The Value expression for textbox “CompanyInfo” refers to the field ‘PricesInclVAT_YesNo’. Report Item expressions can only refers to fields within the current data set scope more