Runtime error in the ATM problem (using pyhton 3.6)

x,y = map(float,input().split(" "))
if (x<y) and (x%5 == 0):
m = y-(x+0.50)
print(round(m,2)) #also tried %.2f,%m
else:
print(y)

This is my code and I’ve tried multiple variations of the logic but codechef doesn’t seem to accept any. After a successful run, it shows NZEC error after “submitting”. Please tell me how can I modify?

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