Your assumption that HK doesn't have any autonomy might have something to do with that ;)
As to what she could do: she can do a lot; the protestors have a list of 5 demands, one of them is the withdrawal of the extradition-bill. She could comply with that, for example.
Their demands also include permanent legislative independence from China. Something they obviously don’t have today, and will have less and less as China continues it’s stated policy of continuing the complete integration of Hong Kong into China.
Any level of autonomy Hong Kong has is granted entirely at the discretion of China, and is only temporary in any case, as it has an expiry date. It’s exceedingly obvious to any observer that Hong Kong does not currently have sufficient autonomy to satisfy the protestors demands.