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Unable to figure out how to resolve the contraction / reduction conflict

I am trying to create a grammar for the GNU MathProg language from the glpk package https://www3.nd.edu/~jeff/mathprog/glpk-4.47/doc/gmpl.pdf
Unfortunately, the grammar that I have written so far is ambiguous. I do not know how to tell the bison which branch of the parsing tree is correct when some kind of identifier is used. For instance:

numericExpression : numericLiteral
              | identifier
              | numericFunctionReference
              | iteratedNumericExpression
              | conditionalNumericExpression
              | '(' numericExpression ')' %prec PARENTH
              | '-' numericExpression %prec UNARY
              | '+' numericExpression %prec UNARY
              | numericExpression binaryArithmeticOperator numericExpression
              ;

symbolicExpression : stringLiteral
               | symbolicFunctionReference
               | identifier
               | conditionalSymbolicExpression
               | '(' symbolicExpression ')'  %prec PARENTH
               | symbolicExpression '&' symbolicExpression
               ;

indexingExpression : '{' indexingEntries '}'
               | '{' indexingEntries ':' logicalExpression '}'
               ;

setExpression : literalSet
          | identifier
          | aritmeticSet
          | indexingExpression
          | iteratedSetExpression
          | conditionalSetExpression
          | '(' setExpression ')'  %prec PARENTH
          | setExpression setOperator setExpression
          ;


numericLiteral : INT
           | FLT
           ;

 linearExpression : identifier
             | iteratedLinearExpression
             | conditionalLinearExpression
             | '(' linearExpression ')'  %prec PARENTH
             | '-' linearExpression  %prec UNARY
             | '+' linearExpression  %prec UNARY
             | linearExpression '+' linearExpression
             | linearExpression '-' linearExpression
             | linearExpression '*' numericExpression
             | numericExpression '*' linearExpression
             | linearExpression '/' numericExpression
             ;

logicalExpression : numericExpression
              | relationalExpression
              | iteratedLogicalExpression
              | '(' logicalExpression ')'  %prec PARENTH
              | NOT logicalExpression %prec NEG
              | logicalExpression AND logicalExpression
              | logicalExpression OR logicalExpression
              ;

identifier : SYMBOLIC_NAME
       | SYMBOLIC_NAME '[' listOfIndices ']'
       ;

listOfIndices : SYMBOLIC_NAME
    | listOfIndices ',' SYMBOLIC_NAME
    ;

An identifier is simply a variable name. A variable has a specific type (parameter, set, decision variable) and can be indexed. In the encoder, the programmer must declare the type of the variable in expressions such as for example.

param p1;
param p2{1, 2} >=0;
set s1;
set s2{i in 1..5};
var v1 >=0;
var v2{S1,S2};

But when the bison sees that the identifier does not know which rule should be used, and I get decrease / decrease conflicts, for example

113 numericExpression: identifier .
123 symbolicExpression: identifier .

'&'          reduce using rule 123 (symbolicExpression)
ELSE         reduce using rule 113 (numericExpression)
ELSE         [reduce using rule 123 (symbolicExpression)]
INTEGER      reduce using rule 113 (numericExpression)
INTEGER      [reduce using rule 123 (symbolicExpression)]
BINARY       reduce using rule 113 (numericExpression)
BINARY       [reduce using rule 123 (symbolicExpression)]
ASIGN        reduce using rule 113 (numericExpression)
ASIGN        [reduce using rule 123 (symbolicExpression)]
','          reduce using rule 113 (numericExpression)
','          [reduce using rule 123 (symbolicExpression)]
'>'          reduce using rule 113 (numericExpression)
'>'          [reduce using rule 123 (symbolicExpression)]
'}'          reduce using rule 113 (numericExpression)
'}'          [reduce using rule 123 (symbolicExpression)]

113 numericExpression: identifier .
123 symbolicExpression: identifier .
130 setExpression: identifier .

UNION           reduce using rule 130 (setExpression)
DIFF            reduce using rule 130 (setExpression)
SYMDIFF         reduce using rule 130 (setExpression)
ELSE            reduce using rule 113 (numericExpression)
ELSE            [reduce using rule 123 (symbolicExpression)]
ELSE            [reduce using rule 130 (setExpression)]
WITHIN          reduce using rule 130 (setExpression)
IN              reduce using rule 113 (numericExpression)
IN              [reduce using rule 123 (symbolicExpression)]

,

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1

, identifier :

numericExpression : identifier
symbolicExpression : identifier
setExpression: identifier

. - ( ):

symbolicExpression : SCALAR_NAME
setExpression: SET_NAME

. ,

numericExpression : identifier

AMPL , , MathProg, AMPL, symbolicExpression numericExpression.

, -, , ​​ , , .

flex , , - :

return is_setname(...) ? TOK_SET_NAME : TOK_SCALAR_NAME;

is_setname - , . ​​ .

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