Autojump not working

Put the summary of the bug you're having here

What I expected to happen was...:
to be able to walk and jump

What actually happened was...:
Autojump to work (is set to on), or if using w to move and hit spacebar to be able to jump up one block

Steps to Reproduce:
1. Was walking press spacebar and nothing happened.  If I hit spacebar and then W I can usually move forward then
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