My scrambler 400x tank had .5L of fuel already. I went for a full tank till neck and filled 13.32L.

my bike now has 13.82L. is this possible? Or is it a scam? I asked with petrol pump owner and triumph service guy. They both gave similar answers saying that 13L tank capacity is below neck of tank cap. But I have filled much more than it. Whats your opinion guys? Is it a scam or not?