that seems your config file was corrupted, please wait nas finish booting and see web login page.
find a small hole at the back of nas that is reset button.
try press and hold it for 10 sec while nas is power on, you suppose to hear 2 beep.
then your nas will reset user name and password as default (admin/admin) and your network will reset as dhcp.
you can download Qfinder to find your nas ip
this behavior will NOT wipe your data
after reset nas, you can login web admin page to add share folders back one by one as pics attached.