Just need some help, bought above router and despite following exactly from the instruction provided unable to connect to unifi.

on the sticker outside box stated can use unifi and inside got 1 piece of paper on config.

using supplied unifi router everything works normally. username n psswrd confirm okay ,couldn't get to D-link helpline tech support.
Thanks.

There's separate piece of paper included inside on how to set it for unifi. Followed it to the letter n won't work.
By ur 2nd statement does it means from modem to supplied router then to dir 850l ?
Sorry not to tech savvy :(

attached scan image of setup instruction. there's no latest firmware from d-link website.