Spreadsheet - If else Script

Question

Anyone can help me find the error of the script.

function Notes() {

  var ss=SpreadsheetApp.getActive().getSheetByName('Sheet3');
  
  var value=ss.getRange(A1).getValue();

  if (value = 'Metal'){

     ss.getRange(B2).setValue("Plastic Note");}

  else if (value = 'Metal'){ 

       ss.getRange(B2).setValue("Metal Note");}
     
 else if (value = 'Tubes'){
     
         ss.getRange(B2).setValue("Tubes Note");}
     }