As someone who used to identify as one; calling yourself a "Libertarian Marxist" is the stupidest shit.

To label yourself a Marxist is to imply that you have adopted Marx's scientific method of socio-economic analysis, Historical Materialism.

If you believe that Marx was a Libertarian, the term "Libertarian Marxist" would be redundant.

If you believe that Marx was too "authoritarian", "Libertarian Marxist" would be an oxymoron.

The term is a contradiction, which is why the only people who call themselves Libertarian Marxists today are Liberals who wish to adopt the aesthetics of radicalism; but are unable to escape from Bourgeoise propaganda surrounding actually existing Marxist revolutions, and Marxist States.