Help with my arrest record

[kngln]

What is the name of your state (only U.S. law)? not in the US

I tried to enter USA from Calgary Airport, Canada a few months ago. I was
carrying a pack of Chinese herb powder. The USA officers tested the powder and suspect it's
drugs. I was then handed to the Canadian authorities and was detained
for a night until an RCMP officer came and did some more tests on the
herb. The tests showed negative results. I was released on the next morning. I was not given any documents regarding this arrest. The Canadians didn't fingerprinted me, but the USA officers did.

Later I tried to apply for a tourist visa for the USA and I was told
that they have a record of "found with drugs" under my name. My visa
application was denied.

How can I clear my name?

Thanks in advance.