Feedback and a few comments

In general, there are no problems, but buying by a limit order takes a very long time. The first transaction was over 30 minutes. Not enough quick purchase on the market. Also, the button with the balance and the deposit is not very conveniently placed. It would be better from above.
Testnet: ST394HY93ZY49EDHP0JAG74EYK59THY8JJHA85NER Mainnet: SP394HY93ZY49EDHP0JAG74EYK59THY8JJG5XP9T7

That is because your order is not matched on the other side, once it is matched, the transaction happens immediately.