I’m trying to create a project that has too many sheets, so to easily navigate through those sheets, I decided to create a drop down list with all of the sheet names and to create a button to go to the selected sheet.
dropdown list with the button to access other sheets

Below is my script:

function openTab() {
  var ss=SpreadsheetApp.getActiveSpreadsheet();
  var form=ss.getSheetByName("REGISTRY");
  var landing=form.getRange("I11").getValue();
  var datasheet=ss.getSheetByName(landing);
  datasheet.activate();
}

When I try to run this script, it returns this error:

TypeError: Cannot read properties of null (reading ‘activate’)

“REGISTRY” is the name of the sheet which has the dropdown, and “I11” is the exact cell where the dropdown is located.