private String editUserPermission(Operation op, Permission permission, IUser user) {
   DiscordUser u = cacheService.findUserById(user.getID()).orElseGet(() -> new DiscordUser(user));
   changePermission(op, permission, u);
   u = cacheService.saveUser(u);
   log.info("Saving new user permission settings: {}", u);
   permissionService.evict();
   return String.format(
       "Modified user %s: %s permission %s",
       u.getName(), op.name().toLowerCase(), permission.getName());
 }