No path to transform

[Ofnuts]

That means that your transform tool is set to act on paths. See the "Transform" line at the top of the Tool options, there are four icons, from left to right, that set what is transformed:

• Layer: the active layer (the options you want)
  
• Selection: the selection mask (and not the selected pixels)
  
• Path: the current path (the one you likely have set by mistake)
  
• Image (since 2.10.14): transforms the whole image (and not just the active layer)
  

See https://docs.gimp.org/en/gimp-tools-tran...-transform