Unhandled promise rejection

在部分IOS手机发现如下问题，调试无果，请大神指点

客户端信息

相关代码

/**  * 会员登录  */ async userSignin(params) {     const that = this;     const json = await api.userLogin({         query: params     });     if( json.code == 0 ){         if( util.empty(json.HTTPHEADER['Set-Cookie']) == false ){             // 登录成功保存身份验证cookie             this.$parent.setApiCookie(json.HTTPHEADER['Set-Cookie']);         }         // 保存会员信息         this.$parent.globalData.memberInfo = json.data;         tip.toast('登录成功', function(){             that.gotourl(that.gourl);         }, 'success', 1000);     }else if(json.code == 80002){         // 手机号未注册         this.is_register = true;         this.$apply();     }else{         this.showZanTopTips(json.msg);     } };