Ok So I bought coins that are now expired.
Can you give more explanation? In this time I will assume if you've bought the coin in the past time which not gets more development on the coin in this time.
Does that mean that they cannot be traded and I have lost all the Bitcoin I invested in them?
Can you tell me about your coin?
But, The right answer if your coin still can be tradable on the exchange site if your coin still supporting some of the exchange sites.
You can go to the market cap and try to search the list of your coin and open the market tab. This will be applied if your coin has listed on the coinmarketcap.