Yep all you should have to do with selection tool is double click. If you have text tool selected, then single click.
Thanks for your feedback.
Yes, to edit text all you need to do is double-click on the text object with the Select tool. However, if it's in a group or repeat group, you may have to double-click on it twice (depending on grouping level): once to enter edit context for the group (to select the object you double-clicked on), and once again to actually edit the text. If it's in a group, you can save a double-click by holding down Cmd and clicking on the text object to select it, and then double-clicking on it.
If you'd like additional text features, feel free to peruse and up-vote what's already been suggested in UserVoice, or add a new suggestion here: Adobe XD: Feature Requests: Top (59 ideas) – Adobe XD Feedback : Feature Requests & Bugs
Thanks for the quick reply Joe!
I ended up just recreating the text blocks. It appears that I somehow converted the other text blocks to an object. Kind of like a CMD-T in photoshop. Once that was done, I could no longer edit the text. I wish I knew how that happened so that I can avoid it in the future.
It is not easy to see if it is in a group or not. How can I tell. Chances are that is exactly what happened. However, since I have already deleted them I can't find out.
I do know that I created one from the other by using a key combination (cmd + opt) and dragging. As an experiment, I tried that with some sample text and was able to edit them both with no problem.