go to this page
https://www.fantasymanager.co/join/?cid=kvrzx23 then click the log in button that should bring up your team, then click the transfers button at top of the page that should bring up your current team with 4 boxes on the RHS under the word Transfers, the boxes are labelled Goalkeepers (Pink), Defenders (Blue), Midfielders (Orange), Forwards (Green)
If you want to make a transfer of say your Goalkeeper klick on the box marked Goalkeepers and a drop down will give you 3 choices for goalkeepers, if you have Cooper as your goalie and you want to change him, then click on the remove button beside his name and the little green checkmark will disappear and then click on which goalie you want. if you want to do more transfers then open each box and make your changes. Once you have finished your transfers then click on the black button on LHS that says Save Team and you are done.
It works fine for me.