Thanks for your reply Mabel! Sorry it took so long to reply.
Here is the "Post" content type. Below that is the json definition of the Flow, and below that, the json of the error message.

{
"$connections": {
"value": {
"sharepointonline": {
"connectionId": "/subscriptions/3200b703-8ae2-4bd4-9c66-dcd3bf335cd2/resourceGroups/Redacted-Tasks/providers/Microsoft.Web/connections/sharepointonline",
"connectionName": "sharepointonline",
"id": "/subscriptions/3200b703-8ae2-4bd4-9c66-dcd3bf335cd2/providers/Microsoft.Web/locations/northcentralus/managedApis/sharepointonline"
}
}
},
"definition": {
"$schema": "https://schema.management.azure.com/providers/Microsoft.Logic/schemas/2016-06-01/workflowdefinition.json#",
"actions": {
"Create_HTML_table": {
"inputs": {
"columns": [
{
"value": "@item()['dynamicProperties']"
},
{
"value": "@item()['ItemInternalId']"
}
],
"format": "HTML",
"from": "@body('Get_items')?['value']"
},
"runAfter": {
"Get_items": [
"Succeeded"
]
},
"type": "Table"
},
"Get_items": {
"inputs": {
"host": {
"connection": {
"name": "@parameters('$connections')['sharepointonline']['connectionId']"
}
},
"method": "get",
"path": "/datasets/@{encodeURIComponent(encodeURIComponent('https://redacted.sharepoint.com/sites/redacted/news/'))}/tables/@{encodeURIComponent(encodeURIComponent('Posts'))}/items"
},
"runAfter": {},
"type": "ApiConnection"
}
},
"contentVersion": "1.0.0.0",
"outputs": {},
"parameters": {
"$connections": {
"defaultValue": {},
"type": "Object"
}
},
"triggers": {
"Recurrence": {
"recurrence": {
"frequency": "Minute",
"interval": 15
},
"type": "Recurrence"
}
}
}
}{
"status": 400,
"message": "The query to field 'NumComments/PostTitle' is not valid.\r\nclientRequestId: 026ba1a4-145e-40f3-8527-59ac4b5ad5bb",
"source": "https://redacted.sharepoint.com/sites/redacted/news//_api/SP.APIHubConnector.GetListItems(listName='Posts',queryOptions=@q)?@q=''",
"errors": [
"-1",
"Microsoft.SharePoint.SPException"
]
}