RB750GL Upload Problem. Need help

Greetings …
I have a big problem here, i bought RB 750GL to bound a connection from 3 ISP
and i have three ADSL connection
1- 4Mega
2- 1 Mega
3- 1 Mega
i merge these with the RB750 GL and Download is working Fine and take speed from the three routers

but when i try to upload .. i face a problem .. the upload go from 1 router not from the three routers
which mean i only get connect to one service

Ex; when i connect FTP and upload 1st file it goes and upload with the 1st router 4M speed
my 2nd file at the same time go to the 2nd router the 1M speed
the 3rd file at the same time go to the 3rd router the other 1 M speed.

my question is how i upload with Full Speed to the three routers 6Mega for my 1st connection?
i need all speed to my connection.

i will be waiting for any assistance… i wish that i explained my problem well.

thanks in advance.

Deleted because not related.

Thank you Very Much For Reply
i was sure i’m in Wrong way :frowning: but hoping someone will telling me i’m right

but i will try to correct it as much as i can… for now

1- i take All internet accounts from one ISP
2- i don’t know how i can know that my router supporting MLPPP.
3- about the company i will call them to ask about this service.

for now i will check the links and read the pdf. thank you so much and maybe i will back to you later.

thank you dear friend

Yours
yousef

:frowning: I Failed and i lost hope. i contacted the ISP and they didn’t support Upload speed more than 1024k :frowning: and Merging using MLPPP i didn’t understand it so i think my only way is getting lease line. and it is very expensive here in EGY.
if there is any solution i will be very thankful