I created an animation, and all is fine except teh rendering.
Before I rendered a draft successfully, now when pressing F12 it shows the image of that frame of the draft, but it won’t start rendering the scene anew.
No blend file supplied with your post so we can only go with guess work and you doing the actual checking.
Check the render settings
Check the Render layers setings
Check you have nothing loaded in the Video Sequencer or Compositor that you don’t want (Delete what you don’t want or disable them in the Render / Post Processing panel)