Common attributes for multiple schema files

Can someone help me with a way to add a common attribute to multiple flow schemas?

I have different schema files for different task types which are responsible for attributes of those tasks. I want to add a common attribute to all the schemas, but if I do so I get following error:

Adding attributes from frontend by:

const modeler = ModelerService.getModeler();
const modeling = modeler.get('modeling');
const attrInfo = {};
attrInfo[key] = value;
modeling.updateProperties(el, attrInfo);

Here, key is the attribute name and value is the attribute value.

Schema file:

{
“name”: “voice”,
“uri”: “http://some-company/schema/bpmn/ivr”,
“$schema”: “http://json-schema.org/draft-07/schema”,
“description”: “Properties for the voice file”,
“prefix”: “voice”,
“xml”: {
“tagAlias”: “lowerCase”
},
“types”: [
{
“name”: “voiceFile”,
“extends”: [
“bpmn:Task”
],
“properties”: [
{
“name”: “taskType”,
“description”: “This variable tells what type of task it is”,
“isAttr”: true,
“type”: “String”
},
{
“name”: “taskName”,
“description”: “hold task’s name”,
“isAttr”: true,
“type”: “String”
},
{
“name”: “isDisabledVoice”,
“isAttr”: false,
“description”: “tells if the element is disabled”,
“type”: “String”
}
]
}
],
“emumerations”: ,
“associations”:
}