How did you link your accounts?

Account 1 = Boosting character
Account 2 = leveling
Account 3 = leveling
Account 4 = leveling
Account 5 = leveling

If you did
Account 2 --> Account 3 --> Account 4 --> Account 5
Account 1 = Not linked at all
It should work.

If you did:
Account 1 --> Account 2 --> Account 3 --> Account 4 --> Account 5
It used to work, not sure if it works now though.

If you did:
Account 1 ---> Account 2 , Account 1 --> Account 3 , Account 1 --> Account 4 , Account 1 --> Account 5
It won't work at all.