Get list of forms with specific tag

i am tagging kobo forms using specific unique tags however when i try to retrieve the forms that contains such tags i get all forms that i have on the kobo server. it used to work before but doesnt anymore…

this is how the code looks like
string GetTagInfoURL = https://kc.kobotoolbox.org/api/v1/forms?tags=" + formid;
var client2 = new RestClient(GetTagInfoURL);
client2.Authenticator = new HttpBasicAuthenticator(uname, pwd);
var request2 = new RestRequest(Method.GET);
IRestResponse response2 = client.Execute(request2);
Please help