Taylor Swift is America's sweetheart, but she's facing some real trouble (wubble, wubble) in America's hat. She's being sued in Canada!

TMZ reports that Swift was paid $2.5 million up front to headline a huge country music festival in Ottawa, Canada. The festival, called the Capital Hoedown, was set to go down in August 2012 -- but it never happened ... and Swift kept all of her cash.

Since Swift still has her $2.5 mil despite not having to show up or perform, the ticket company for the hoedown is requesting that Swift pay back the $1.8 million in ticket sales that need to be refunded to the buyers. This would essentially still let her get $700,000 profit despite not having to show up or do anything. Not a bad deal, right?

However, Swift's rep insists she has no deal with the ticket brokers -- and that no one in her camp has seen the lawsuit yet. We have a feeling that there will be attorneys with microscopes looking over this contract to seek any, and every possible loophole.

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