If this is for your school work then I cannot answer but if this is for your everyday conversation "surprisingly" is very common to use. I don't think I've ever heard someone say surprisedly. Surprisingly, Surprisedly is a word!

The answer is "surprisedly". But in spoken language we would probably say "in surprise". "Surprisingly" is not a manner of doing something. It is used to say that some information is surprising. E.g. "That article was surprisingly interesting". "He is surprisingly tall". Or "Surprisingly, he has never been to London".