There are many potential causes of bloating after meals. If this started after an abdominal surgery the potential for partial obstruction should be ruled out. This is typically done with a small bowel series but an abdominal and pelvic CT scan would also be appropriate. Delated gastric emptying could be an issue as well and is readily measured with a simple test. In brief, a thorough and thoughtful evaluation would be expected to provide a reason.
Thank you for responding if only I can get a doctor to want to do all those things