I see!
Well, the groups in Analyze tab are generated from tags of datasets.
When you create a new dataset and assign a title to it, the same value it set as dataset tag.
If you change the dataset title, it is not propagated to the corresponding tag.
The only existing workaround is to export LDM, update tags according to dataset titles and put the LDM back. Personally I would do it with our Python SDK, just a few lines of code should do the work. I can help you implement it, if you are interested.
Please, anyone from GD, who can do it, register this request to our ProductBoard.