Hi @TexasBI,
I have made a test on my side and please take a try with the following workaround:
- Add a proper trigger, here I use Flow Button trigger.
- Add a "Get rows" action, specify Table name.
- Add a Variables-> "Initialize variable" action, Name set to ItemsArray, Type set to Array and Value set to empty.
- Add a "Apply to each" action, input parameter set to output of the "Get rows" action.
- Within "Apply to each" action, add a Compose action, Inputs set to following formula:
{
"FieldValues": {
"Customer": Customer dynamic content of the "Get rows" action,
"Amount":Amount dynamic content of the "Get rows" action,
"Quantity":Quantity dynamic content of the "Get rows" action,
"Start Date": Start Date dynamic content of the "Get rows" action,
"End Date": End Date dynamic content of the "Get rows" action
}
}

Add a "Append to array variable" action, Name chose ItemsArray and Value set to output of the "Compose" action.
- Under "Apply to each" action, add a "Compose 2" action, Inputs set to following formula:
{
"Invoice Name":"My Invoice",
"Description":"My Description",
"Items":ItemsArray variable
}

Image reference:


The flow works successfully as below:
The output of the "Compose 2" action as below:
{
"Invoice Name": "My Invoice",
"Description": "My Description",
"Items": [
{
"FieldValues": {
"Customer": "Bob",
"Amount": "10",
"Quantity": "5",
"Start Date": "2018-05-01T00:00:00Z",
"End Date": "2018-05-02T00:00:00Z"
}
},
{
"FieldValues": {
"Customer": "Joe",
"Amount": "11",
"Quantity": "2",
"Start Date": "2018-05-03T00:00:00Z",
"End Date": "2018-05-04T00:00:00Z"
}
}
]
}
Best regards,
Kris