Why does my phone ask me to 'Rotate Phone' or 'Rotate to Draw' when signing?

When signing on a mobile browser, you may be prompted to rotate your phone to draw the signature. If you are unable to rotate your phone from Portrait orientation to Landscape orientation, you may need to enable auto-rotation on your device. 

Here are instructions for enabling auto-rotation on some common devices - if your device is not listed or the steps differ, please check with the manufacturer for instructions. 
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