When snap to grid is on, it will only create new text. It won't select existing text for editing - probably because it isn't on the grid. This never used to happen before the latest update.
Please get in touch with us at any of the other support channels – https://helpx.adobe.com/support.html . Since this is not a generic issue that we can reproduce at our end, we will need someone to look into your machine to figure out what is going on here.
With Best Regards,