Why I invested $X but my portfolio value is now $Y?
The price that you see in portfolio value is calculated based on the current Orderbook secondary market price. Orderbook secondary market liquidity and volume is very limited, therefore the price is often goes down when too many people try to cash out or sell the stock at the same time.
The good news is that secondary market sale is not the only way to liquidate your stock. Each tokenized stock is backed by the underlying paper stock, which, in most cases, does not have live secondary market at all. When the underlying company goes public (does IPO), we (UTC.fund) sell the underlying stock and pay out the proceeds to the token holders based on the price of sale of the underlying stock. That price, in most cases, is higher than the price you would get from Orderbook secondary market.
Orderbook secondary market uses SushiSwap v2 liquidity pools on the backend. You can verify the prices in the pools via coinmarketcap.com and other blockchain explorers.