This is how I can reproduce the problem:
I make the "Land Revision" fail on purpose, then I go to the corresponding lease and see a Slot Lock is still there:
{F1027069}
Then I resolve the conflicts and click "Land Revision" again, I see it just keeps running. I go to its lease and see it "Waiting for Activation" due to no resource:
{F1027075}
Then I go to the previous locked lease and manually release it:
{F1027082}
Then the waiting lease can get the resource and proceed.