Can't connect with WinBox

Hello. I recently bought the Mikrotik RB5009. I tried setting it up, i connected to it with a MAC address through WinBox. I played around with few things trying to get it to work. It disconnected and now I can’t get connect back to it and it doesn’t show up in the neighbors list. I tried holding down the reset button but nothing seems to work.

Did you try this:

Buttons and jumpers
The RouterBOOT reset button has the following functions. Press the button and apply the power, then:

Release the button when the green LED starts flashing, to reset the RouterOS configuration to defaults.
Release the button after LED is no longer lit (~20 seconds) to cause a device to look for Netinstall servers (required for reinstalling RouterOS over the network).
Regardless of the above option used, the system will load the backup RouterBOOT loader if the button is pressed before power is applied to the device. Useful for RouterBOOT debugging and recovery.

I would also recommend you to read this:

https://forum.mikrotik.com/viewtopic.php?p=1017165&hilit=New+user#p1017165

So it turns out I wasn’t pushing the button hard enough. I got it to load the default config and that seems to have fixed it