Hi Nick, 

Thanks for posting in the Lucid Community! There are a few reasons why this could happen:

• Is it possible that the sticky notes you are unable to resize into a rectangle have been locked up? This may be the case if you’re collaborating on a document or working on a doc created from a template. You can check this by right-clicking the sticky note > selecting the Lock/unlock option from the dropdown > seeing if any of the options Lock and/if Lock size and position is enabled.  
  
   

  

• Is it possible that your sticky notes’ aspect ratio has been locked up? Please note– this would only be the case if you are working on Lucidchart. You can check this by selecting the sticky note > navigating to the shapes option menu at the top > seeing if the padlock icon between “Width” and “Height” is bluish, which indicates it’s enabled.
   

  

If that’s not the case, could you reply to this post with a screenshot of what you see when trying to resize the sticky note so I can take a closer look? Thanks! 

Thanks!  I hadn’t spotted that the dimensions were locked on the Shape Options dialog