Ok, looks like you will have to perform a factory reset. The user manual documents the factory reset procedure, but the quick version is:
– power off the controller, then power it back on, and as soon as you see ‘OpenSprinkler’, press and hold the first push button B1, continue holding B1 until the LCD screen displays ‘Factory reset?’. Make sure the answer is ‘Yes’. Then press and hold the third push button B3 until the controller reboots and completes resetting. The port will be recovered to 80. As robi said, use a port above 1024. For example, 8000, 8080, 8888 etc are pretty common ones.