Make a PHP script to authenticate on encrypted app

I need somebody to write me a PHP script to authenticate on a specific app.

This is how the data is encrypted before being sent to the server

['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', 'H6yYWMof28604m6PcyOHBNJNhf+JWTXp6h0JecHLui3dWD7TUemCAOZxrv8=', '1b7H3j9WRv3f4XvCmBTsGIQK4Zd3jUmj3OBTfYvBqqZmtHUjEfKX3dPSv6k=']