I applied my overpayment to 2019 I then filed form 1040X which shows that I owe, but the corrected 1040 shows that I would have less applied to 2019. Which is correct

[fanfare]

Do not include your old 1040 nor your revised 1040 because the Form 1040X reflects any changes there and becomes your new tax return.

Include any new/corrected document only if it shows federal tax withheld, and include in order only those Sequence Numbered tax forms and Schedules that changed or were added due to your amendment. 

Attachment Sequence Number is on all the forms and Schedules that come after 1040.

Mail to the address shown for your location in the Instructions for Form 1040X.

[fdeaners57]

Both are correct.  Your original 2018 1040 filing displayed a net overpayment which was applied to 2019.  Since your 2018 1040X modified your tax activity indicating you didn't overpay (you owe), you have no overpayment to rollover (apply) to 2019.

[fanfare]

no, the returns are processed separately. The amount applied to next year will remain unchanged.

[fdeaners57]

Both are correct.  Your original 2018 1040 filing displayed a net overpayment which was applied to 2019.  Since your 2018 1040X modified your tax activity indicating you didn't overpay (you owe), you have no overpayment to rollover (apply) to 2019.