Maybe you need to wait for it to get rejected from itself.
Actually it depends on which api they are using to monitor the network.
Unless that network gets propagated fully, you'll have to wait.
It's been over a week and it's been rejected twice as far as I can tell. The message I see when I follow it to blockchain is
"Transaction rejected by our node.
Reason: Transaction was previously accepted but has been pruned from our database"
However, in coinomi it is still greyed out waiting for confirmation. I'd like to find some way to cancel it and send it again with the correct transaction fee.
It seems like it has been cancelled on blockchain.info but it isn't cancelled in coinomi.