I have undergo an ecg procedure and it shows unconfirmed diagnosis, what does it mean?

Any testing must be interpreted by the physician who knows your history, exam and other testing data. By itself, the wording just means nothing on the test was conclusive for ab=ny diagnosis. Whether this was from a poorly done test or it just had no unusual features cannot be determined by your post.

Many such tests are non diagnostic as they cannot be used to confirm a specific presumptive diagnosis as suggested by symptoms and physical exam. These tests remain important as they rule out conditions and help in further continuing work up in order to find the correct diagnosis, your gastroenterologist remains your best reference in suggesting further tests.