If you are seeing an error message related to not having an entry on line 18 of Schedule SE, you are correct in thinking this is related to deferring self-employment taxes.
If you do not want to defer any of the self-employment tax, then enter '0' for line 18.
That should clear the error message and specify that you do not wish to defer any of the SE tax. If you are seeing a different type of error message, please add some more details for more possible assistance.
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