Sum 15
Sum 15 is read as a call for caution in your affairs and a warning about dishonesty.
Interpretation
The traditional meaning is: be careful — someone involved in your affairs is not acting in your interest. The sum does not promise failure; it warns you to check.
In questions about money it reads as a risk of loss through someone else’s bad faith — or through your own inattention to the terms.
Probability
Three dice give 216 equally likely outcomes (6 × 6 × 6). A sum of 15 comes from 10 of them, or 4.6%.
For comparison: the most frequent sums, 10 and 11, come up 12.5% of the time, and the rarest, 3 and 18, 0.46% of the time.
The closer a sum is to the middle, the more often it comes up, and the traditional interpretations take this into account: the extreme sums have the sharpest meanings.
Advice
Reread the terms, the contract or the correspondence. Sum 15 points to a detail you have missed.