Compile error: Sub or Function not defined

I've started to record a simple macro to automate the use of Solver however the macro will not run due to the error message "Compile error: Sub or Function not defined" (see attached). The macro doesn't start and stops with the first line highlighted "SolverReset". Other macros with similar use of Solver do not have a problem. Appreciate any help regarding this problem.

Sub Macro1()
'
SolverReset
    SolverOk SetCell:="$C$81", MaxMinVal:=2, ValueOf:="0", ByChange:="$C$59:$C$64"
    SolverAdd CellRef:="$C$84", Relation:=2, FormulaText:="sum($C$85:$C$89)"
    SolverOk SetCell:="$C$81", MaxMinVal:=2, ValueOf:="0", ByChange:="$C$59:$C$64"
    SolverSolve
End Sub