---

@app.route(f"/{ACCESS_KEY}/doubleCheck", methods=["GET", "POST"])
def double_check():
    try:
        phone = request.form.get("phone")
        if request.method == "POST" and request.is_json:
            phone = request.json.get("phone", phone)

        if not phone:
            return jsonify({
                "error": "bad_request",
                "error_description": "Parameter 'phone' is required"
            }), 400

        if not phone.startswith(("7", "8", "+7", "+8")):
            return jsonify({
                "error": "bad_phone_format",
                "error_description": "Phone must match format 71234567890 / +71234567890"
            }), 400

        phone_clear = phone.replace("+", "")
        phone_clear = phone_clear.replace("-", "")
        phone_clear = phone_clear.replace("(", "")
        phone_clear = phone_clear.replace(")", "")
        phone_clear = phone_clear.replace(" ", "")
        lg(f"new request: \nPhone: {phone}")
        duplicates_found = checker_btx(phone, phone_clear)
        lg(f'"result": {duplicates_found}')
        return jsonify({"result": duplicates_found})

    except Exception as e:
        return jsonify({
            "error": "server_error",
            "error_description": str(e)
        }), 500