Rent collection total sum split by all tenants

My landlady has now the rent collection service. We are 3 tenants and the email says we must pay the total sum of the flat (3 tenants rents). I would love to know how to split the total rent so each one of us pay our own rent directlyto Openrent rent using the link on the email?
Many thanks!

OpenRent can accept partial payments, so I see no reason why all three tenants can’t set up a Standing Order for their share to arrive say three days before the payment due date to avoid reminder emails. Three days allows for Bank Holiday delayed payments - 4 would be better.