GSOn error Expected a string but was BEGIN_OBJECT when parsing JSON response

Create a modal with the values of JSON result like

    public class Customer {
        private String oid;
        private String id;
        private String name;
        private String timestamp;
        private String email;
        private String modified;
        private String url;

        public String getOid() {
            return oid;
        }

        public void setOid(String oid) {
            this.oid = oid;
        }

        public String getId() {
            return id;
        }

        public void setId(String id) {
            this.id = id;
        }

        public String getName() {
            return name;
        }

        public void setName(String name) {
            this.name = name;
        }

        public String getTimestamp() {
            return timestamp;
        }

        public void setTimestamp(String timestamp) {
            this.timestamp = timestamp;
        }

        public String getEmail() {
            return email;
        }

        public void setEmail(String email) {
            this.email = email;
        }

        public String getModified() {
            return modified;
        }

        public void setModified(String modified) {
            this.modified = modified;
        }

        public String getUrl() {
            return url;
        }

        public void setUrl(String url) {
            this.url = url;
        }

        public Logo getLogo() {
            return logo;
        }

        public void setLogo(Logo logo) {
            this.logo = logo;
        }

        private Logo logo;
    }

    public class Logo {
        private int type;

        public String getData() {
            return data;
        }

        public void setData(String data) {
            this.data = data;
        }

        public int getType() {
            return type;
        }

        public void setType(int type) {
            this.type = type;
        }

        private String data;
    }

  Gson gson = new Gson();
 Type listType = new TypeToken<List<Customer>>(){}.getType();
List<Customer> customer= (List<Customer>) gson.fromJson(jsonOutput, listType);