linked accounts not working

Until today I had 3 linked accounts which could all be viewed at once in separate tabs. Today the linking was disabled, as we had been told would happen. However when I open a second tab and try to log in to a second account it simply logs me into the same account I already have open. I expect to see a log-in page for a new account, just as happened before the accounts were linked. One account is permanently linked to my work program and requires uninterrupted access while the others are personal accounts for other family members. I do not want to have to close one account before I can open another, this is unacceptable.