Null response in query for Relay Modern interogation on GraphQL - mongodb

Question

Maybe someone who has managed to pass this step is willing to provide some indications.
I have a schema, a resolver, i request the query and i have a null response.
Please can you help on topic?
module.exports = {
Query: {
allLinks: async (root, {filter}, {mongo: {Links, Users}}) => {
let query = filter ? {$or: buildFilters(filter)} : {};
return await Links.find(query).toArray();
}
and the query request looks like this:
query LinkListPageQuery {
allLinks {
...LinkList_allLinks
}
}
fragment LinkList_allLinks on LinkConnection {
edges {
cursor
...Link_link
}
}
fragment Link_link on LinkEdge {
node {
id
description
url
}
}
My schema looks like this:
const typeDefs = `
type Link implements Node {
id: ID!
url: String!
description: String!
postedBy: User
votes: [Vote!]!
}
interface Node {
id: ID!
}
type Query {
allLinks(filter: LinkFilter, first: Int): [LinkConnection]
node(
id: ID!
): Node
}
type LinkEdge {
node: Link!
cursor: String
}
type LinkConnection {
pageInfo: PageInfo
edges: LinkEdge
count: Int
}
input LinkFilter {
OR: [LinkFilter!]
description_contains: String
url_contains: String
}
}
`;
PS: This language schema is done according to graphql-tools package.
Resolver:
Query: {
users: async (root, { first, after }, { mongo: { Users }, user }) => {
const queryData = await Users.find(query).toArray();
first = first || queryData.length;
after = after ? parseInt(fromCursor(after), 10) : 0;
const edges = queryData.map((node, i) => ({
cursor: toCursor(i+1),
node: node._id,
})).slice(after, first + after);
const slicedUser = edges.map(({ node }) => node);
return {
edges,
pageInfo: {
startCursor: edges.length > 0 ? edges[0].cursor : null,
hasNextPage: first + after < queryData.length,
endCursor: edges.length > 0 ? edges[edges.length - 1].cursor : null
},
count: queryData.length,
};
},
UserConnection: {
edges: ({ edges }) => edges,
pageInfo: ({ pageInfo }) => pageInfo,
count: ({ count }) => count,
},
UserEdge: {
node: async ({ node },data, {dataloaders: {userLoader}}) => {
const user = await userLoader.load(node);
return user;
},
cursor: ({ cursor }) => cursor,
},