Graphql not resolving as expected - node.js

Question

I´m developing a GraqphQL-API which gets the data from MongoDB via Mongoose. Now I have the problem that GraphQL does not use the query to resolve the fields, instead it uses the field resolvers which can't work because there is no ID set.
TypeDefs:
type Query{
getUser(user_id: String!): User
getGroup(group_id: String!): Group
}
type Group {
name: String
scopes: [Scope]
id: String
}
The Resolver:
Query: {
getUser: (root,args,context) => {
console.log(args);
return getUser(args.user_id);
},
getGroup: (root,args,context) => {
return getGroup(args.group_id);
}
},
Group: {
scopes(group){
return getScopes(group.id);
},
name(group){
return getGroupName(group.id);
}
},
The Functions:
exports.getGroup = async (id) => {
const g = await Group.findOne({_id:id});
const scopes = [];
for(let index in g.scopes){
scopes.push({id: g.scopes[index]});
}
console.log(g.name);
return{
name: g.name,
scopes: scopes
};
};
exports.getGroupName = async (id) => {
const g = await Group.findOne({_id:id});
console.log(id);
return g.name;
};
exports.getScopes = async (id) => {
const g = await Group.findOne({_id:id});
const scopes = [];
for(let index in g.scopes){
scopes.push({id: g.scopes[index]});
}
return scopes;
};
The Query:
query getUserGroup{
getGroup(group_id:"5b74c537086152554adf818e"){name}
}
The Result:
{
"data": {
"getGroup": {
"name": null
}
},
"errors": [
{
"message": "Cannot read property 'name' of null",
"locations": [
{
"line": 3,
"column": 5
}
],
"path": [
"getGroup",
"name"
],
"extensions": {
"code": "INTERNAL_SERVER_ERROR",
"exception": {
"stacktrace": [
"TypeError: Cannot read property 'name' of null",
" at _callee2$ (/XXXX/resolver/group.js:20:14)",
" at tryCatch (/XXXX/node_modules/regenerator-
runtime/runtime.js:65:40)",
" at Generator.invoke [as _invoke]
(XXXX/node_modules/regenerator-runtime/runtime.js:303:22)",
" at Generator.prototype.(anonymous function) [as next]
(XXXXX/node_modules/regenerator-runtime/runtime.js:117:21)",
" at step (XXXXX/src/resolver/group.js:5:191)",
" at XXXX/resolver/group.js:5:361",
" at <anonymous>"
]
}
}
}
]
}

Answer 1

const g = await Group.findOne({_id:id});
"TypeError: Cannot read property 'name' of null"
"path": [
"getGroup",
"name"
],
Can you check if g exists or not?