Very smart!

Yes, I just updated the phrase of the wording in the description. Hope it's more clear now.

Fow others who run into this (and maybe to be added to the spec): if both string and symbol keys are present, only update the symbol key.

I'm running into this same issue. Were you able to figure it out? This kata appears to have some serious issues in terms of unclear specifications.

I have no idea what am doing wrong. The last test always fails, but
I think my solution managed to update the both version (the string and the symbol as well).
I use p method to inspect the self:

• before the update: {:enabled=>nil, "enabled"=>true}
• after the update: {:enabled=>false, "enabled"=>false}

That seems just right to me, but the test constantly fails:

Test Failed: Should update key :enabled even if it's 'nil'