A premise that cannot be stated cleanly almost always contains two competing stories. Writers usually experience this as 'it's hard to explain' — but the difficulty is not in the explaining, it is in the script, and readers feel the split within twenty pages even when they cannot name it.
A working premise fuses four things: a specific protagonist, a disruption, a goal, and an obstacle that is ironic rather than arbitrary. Irony here does not mean cleverness. It means the obstacle is the one thing this particular character is worst equipped to face, so the plot is not interchangeable with anyone else's.
Test by comparison, not by taste. Read three loglines for produced films in your genre — real ones, not fan summaries — and put yours in the same line. You are not checking whether yours is better. You are checking whether it has the same shape: one engine, one clock, one central irony.
When the test fails, the fix is subtraction. Pick the story that has the strongest ending and demote the other one to a subplot, or cut it entirely and save it for the next script. Two engines in one chassis do not make a faster car.