Specific to this case
According to your post, you bought seven shares of VBR at $119.28 each on August 23rd. You paid €711,35. Now, on August 25th, VBR is worth $120.83. So you have
$120.83 * 7 = $845.81
But you want to know what you have in EUR, not USD. So if I ask Google how much $845.81 is in EUR, it says €708,89. That's even lower than what you're seeing.
It looks like USD has fallen in value relative to EUR. So while the stock price has increased in dollar terms, it has fallen in euro terms. As a result, the value that you would get in euros if you sold the stock has fallen from the price that you paid.
Another way of thinking about this is that your price per share was €101,72 and is now €101,33. That's actually a small drop.
When you buy and sell in a different currency that you don't actually want, you add the currency risk to your normal risk. Maybe that's what you want to do. Or maybe you would be better off sticking to euro-denominated investments.
Usually you'd do dollar-denominated investments if some of your spending was in dollars. Then if the dollar goes up relative to the euro, your investment goes up with it. So you can cash out and make your purchases in dollars without adding extra money.
If you make all your purchases in euros, I would normally recommend that you stick to euro-denominated investments. The underlying asset might be in the US, but your fund could still be in Europe and list in euros.
That's not to say that you can't buy dollar-denominated investments with euros. Clearly you can. It's just that it adds currency risk to the other risks of the investment. Unless you deliberately want to bet that USD will rise relative to EUR, you might not want to do that.
Note that USD may rise over the weekend and put you back in the black. For that matter, even if USD continues to fall relative to the EUR, the security might rise more than that. I have no opinion on the value of VBR. I don't actually know what that is, as it doesn't matter for the points I was making. I'm not saying to sell it immediately. I'm saying that you might prefer euro-denominated investments when you buy in the future. Again, unless you are taking this particular risk deliberately.