Welcome to this user forum.
As you are not the account holder, its going to be difficult for you to do anything like changing the router, as you would not have access to it. You probably cannot even access the connection information from the home hub.
Whatever you wish to do you must get in touch with your landlord first and obtain his permission.
Replacing the hub is easy once you have access and permission.
Thanks for the reply.
Yes the landlord is ok with the help, she is live in on the ground floor and the issue effects her also.
Then you can get the connection information from the following link, if you post it on this thread, then someone may be able to help.