getting codes from my db is not working. Any advice?

Sound like a syntax-error, but i can not recognize any syntax-errors in my shown code.
If there would be a Syntax-Error → it would be marked in RED

Did you also first imported the wix-data-api ???

import wixData from 'wix-data';

$w.onReady(async function() {
  let RESULTS = await checkData(); 
  console.log("RESULTS: ", RESULTS);
});
  
function checkData(){
  wixData.query("Diamond")
  .find()
  .then((res)=>{return res.items})
  .catch((err)=>{console.log(err);});
}

-Your Collection-Name is → “Diamond” ??? You have already double-checked it?
-Your Collection gives also the related permissions to enter your DATABASE ?
Check all your setup.

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