I have a SharePoint Get Items step in a flow which grabs the data successfully with an ODATA filter of: Audit/Id eq 15

and returns the following data: (only relevant data shown)
{
"@odata.etag": "\"1\"",
"ItemInternalId": "98",
"ID": 98,
"Title": "fsdfsdf",
"Audit": {
"@odata.type": "#Microsoft.Azure.Connectors.SharePoint.SPListExpandedReference",
"Id": 15,
"Value": "Angus Test 1"
},
"Audit#Id": 15,
"Question": {
"@odata.type": "#Microsoft.Azure.Connectors.SharePoint.SPListExpandedReference",
"Id": 31,
"Value": "4.2 (If applicable), did the Subordinate only undertake works delegated to them?"
},
"Question#Id": 31,
"Answer": {
"@odata.type": "#Microsoft.Azure.Connectors.SharePoint.SPListExpandedReference",
"Id": 2,
"Value": "N/A"
},
"Answer#Id": 2,
"Modified": "2024-04-10T16:49:57Z",
"Created": "2024-04-10T16:49:57Z",
However if I set my ODATA filter to: Answer/Id eq 2
I get:

Output error:

The raw output for both these fields is identical in that top result, though Audit/Id refers to a lookup and Answer/Id refers to a choice field.
Can anyone identify why the second filter doesn't work?