Problems with getting shell using UART

Hi, I'm trying to connect to the ZTE H288A using the serial port, but after booting up all I can see is this:

BGA IC
Xtal:1
DDR3 init.
DRAMC init done.
Calculate size.
DRAM size=128MB
Set new TRFC.
ddr-1333

7516DRAMC V1.0 (0)

and then it stops right there, I can't see the full boot process nor can I get a console input, I can see the router login page but I really cant see what I'm missing here, any ideas?

Serial console is disabled?

I don't know for sure, some people get a prompt after the message I've got to hit the (1) for boot, But I didn't get any prompt, just a few lines I posted.

does it use u-boot ?
if so, what does printenv say ?

most likely its a u-boot, I follow instruction from this link https://github.com/mkst/zte-config-utility/issues/43
but after booting the router all I see is a few lines but no prompt.