免费的偶尔能用，但当付费后根本无法。一直与软件提供商沟通，不能得到解决，也不给我退款。我向谁投诉？怎么维权？大家千万不要花钱在这个软件上。Free occasionally works, but not at all when paid for. I have been communicating with the app provider, but I can't get a solution, and I won't get a refund. Who do I complain to? How to protect rights? Don't spend any money on this APP.