Most of the Marriage references say, Somerset and has the spelling as Frances
One does show Allington on Ancestry, but has no document to confirm
You probably have reference to their children, but if not...
Also these baptism transcripts are held in the Milverton, Somerset Records, but reference West Buckland as the parish.
Name: Francis Hyat
[Franciscus Hyat]
Gender: Male
Spouse: Joan Hyat
Child: William Hyat
Date Baptized: 25th July 1769
Somerset, England
Name: Francis Hyat
[Franciscus Hyat]
Gender: Male
Spouse: Joan Hyat
[Joanna Hyat]
Child: Thomas Hyat
Date Baptized: 31st Jan, 1768
Somerset, England
Name: Francis Hyatt
[Franciscus Hyatt]
Gender: Male
Parish as it Appears: West Buckland
Spouse: Joan Jyatt
[Joanna Hyat]
Child: Elenor Hyatt
Date Baptized: 20th Jan, 1766
Somerset, England
Name: Francis Hyatt
[Franciscus Hyatt]
Gender: Male
Parish as it Appears: West Buckland
Spouse: Joan Jyatt
[Joanna Hyat]
Child: John Hyatt
Date Baptized: 12th Mar, 1764
Somerset, England
Name: Francis Hyat
[Franciscus Hyat]
Gender: Male
Spouse: Joan Hyat
[Joanna Hyat]
Child: Maria Hyat
Date Baptized: 28th April, 1771
Somerset, England