How to setup 2 pppoe clients from 1 provider

i have 2 usernames from my ISP and i want to mixed them on my mikrotik RB750GL and create for example 10 users… every 5 users have connection from 1 of these usernames…

username1: test1
username2: test2

ppp secrets usernames: 111;222;333;444;555;666;777;888;999;000
(10 usernames)

username1 = 111;222;333;444;555
username2 = 666;777;888;999;000

Please help i spend dayssss to install and no solution

its not possible

in userman set shared users for every 1 account ..