Average Share prices

When I buy a share of a company at a certain price and later when I buy another share of the same company, why is that my average price change on the trading212 platform? Isn’t that I’m missing some money from the first one? Shouldn’t it be showing individual price rate ? And later if I sell one which one they will remove ? How do they calculate this ? Thank you

3 posts were merged into an existing topic: Buying any selling on trading212