Asking for help

[CPULL]

I am trying to write a Flutter application using this package, to add users to a list I created.
I can get the list and list the items inside, but if I try the createRecord action of atproto.repo I get errors of invalid string conversion.

This is what I am trying to do (and does nto work.) Any help will be sincerely appreciated.

    var record = {
      r"$type": "app.bsky.graph.listitem",
      "subject": userToAddDid, // "did:plc:ln5ldhgxusfjhsinecd4XYZW"
      "list": blocklist, // The list I get from myself as actor
      "createdAt": getNow() // "2025-12-08T15:14:33Z"
    };

    try {
      var _ = await bsky!.atproto.repo.createRecord(
        repo: bsky!.session!.did, // did:plc:4xxvirkcait46ycqpmcuXYZW
        collection: "app.bsky.graph.listitem",
        record: record);
    } catch (ex) {
      setState(() { txt = "ERROR! Cannot add user: $ex"; });
    }

[CPULL]

The exact error I get is "Converting object to an encodable object failed: Instance of 'CheckedAtUri'"