ios 最新sdk 读取不到LCUser的ACL, 修改ACL也经常失败

    LCUser *u = [LCUser currentUser];
    if(u.ACL) {
        //即之前设置过了acl，下次启动app后ACL依然是nil
    }
    else {
        
    }

同样，修改ACL也报错

LCUser *u = [LCUser currentUser];
    
    if (u) {
        
        LCACL *acl = u.ACL;
        //如果没有写权限，先要修改写权限
        if(![acl getPublicWriteAccess]) {
            acl = [LCACL ACL];
            [acl setPublicWriteAccess:YES];
            [acl setPublicReadAccess:YES];
            u.ACL = acl;
            
            [u saveInBackgroundWithBlock:^(BOOL succeeded, NSError * _Nullable error) {
                if (error) {
                   /* 返回错误
                    code = 403;
                    error = "Forbidden writing by object's ACL.";
                  */
                }
                else {
                    //
                }
            }];
        }