Deepseek appears to be running profitably, by being more efficient in how they train their models, being more efficient in how they run their models, and charging a modest profit margin on each API call.
It's a Chinese company in a wild hot technology field that China want to compete in. I bet that they are very well supported by the state. Similar to Llama with Meta's money.
(Source: linked article / interview with the CEO of Deepseek from https://news.ycombinator.com/item?id=42557586)