If you haven't already sold your ALTs simply hold if your project is decent. If the project has no future sell and buy into a decent project. This is all you can do to recover your loss without putting in more money. It will probably take a couple of years to recover your loss!
Some ALTs will never recover from this crash!
It is an ugly situation!
An ugly situation indeed my brother for some altcoins which some have been holding since 2017 and if there is a way one can sell it then it will go far in reducing someone's loss but there is actually no market for them in any of the exchange you visit till today. And it will be a heavy Lost on me if I should sell my ethereum at this moment because I was holding ethereum right from when its was above a thousand dollars in the late 2017.