How to mock the optional ResponseEntity code below for code coverage. Could someone please assist?

public ResponseEntity<Optional> getData(@RequestBody RequestModel requestModel) { try { List mango = new ArrayList();

        mangoRepository.findByMangoTag(
                requestModel.getMangoTag(),
                requestModel.getMangoProduct(),
                requestModel.getSellerType()).forEach(mango::add);

        Optional<Mango> res = mango.stream().findFirst();
        if (!res.isPresent()) {
            return new ResponseEntity<>(HttpStatus.NO_CONTENT);
        }

        return new ResponseEntity<>(res, HttpStatus.OK);
    } catch (Exception e) {
        return new ResponseEntity<>(null, HttpStatus.INTERNAL_SERVER_ERROR);
    }