1. Refer to Creating merge requests: https://docs.gitlab.com/ee/user/project/merge_requests/creating_merge_requests.html
2. Go to Project, select Merge requests from the left menu, and then select New merge request in the upper right corner. See Figure 1.
3. Select the Source branch as your current branch: feature/theme-store-wangqiang, and select the Target branch as the target branch you want to merge into: feature/theme-store. Finally, click Compare branches and continue. See Figure 2.
4. On the form page, edit the Title, Description, and Reviewer, and then click Submit merge request. See Figure 3.
5. The final result page is shown in Figure 4.
6. If you submit another request at this point, an error will occur: The form contains the following error: Validate branches Another open merge request already exists for this source branch: !6989. See Figure 5.
7. You can first close !6989, and then submit again. See Figure 6.
