404 not found e problema de fishing

Hello good afternoon.
The link mentioned above and also located at the end of the message, was made by me in a school project. For unknown reasons, Monday when I entered the site I updated the version of wordpress, and from that moment on, my site was unavailable and giving the error of 404 It was not found and with problems, being impossible now to enter the site admin . The database was not created by me, and only an old professor of mine, in whom I no longer have contact, has access to it.
What can I do to get my website back?
Best regards
Pedro Mota

http://synergy-comunicacao.com/desportoescolar/wp

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