Your issue is with JH or the other tax provider.
To e-file a tax return, you have to authorize the provider to transmit the return, usually by providing an electronic signature. If you signed any agreements with them in writing (paper and ink) those have to be considered as well. Did you authorize them in any way to submit your final tax return?
If so, then you need to find a way to stop them. But if they have already transmitted the return to their server for holding until the IRS is ready, you may be unable to call it back.
If you did not authorize filing, then you should be ok.
If you don't understand your agreement with them you may need to contact a local consumer advocate or the consumer advocacy department of your state attorney general.
