Back button in Lightroom is missing

[lisa16B8]

My back button on Lightroom has dissapeared. Whenever I edit photos, I have an arrow that wipes all the edits I have made and I am unable to delete my last step as the back button arrow is no longer there. Please help

[Rob_Cullen]

Please post a screen-clip of your screen to show 'where' you expect to see a "Back Button arrow".

[dj_paige]

If you click on the step just underneath the most recent step, it removes your most recent step.