Read the popup, then sign
The popup is not a formality. It is the last door in the house. On an EVM chain that door comes in three different shapes, and only one of them is the trade you meant to make.
// what to actually do
- Enter the ETH amount you decided on earlier, not the amount the chart is shouting at you.
- Read what the wallet is actually asking for. A trade moves ETH out and tokens in, and it shows you both sides with a gas figure underneath.
- An approval moves nothing at all. It gives a contract standing permission to spend a token you already hold, at some later moment, without asking you again. That permission survives the trade, survives you closing the tab, and survives you forgetting about it.
- If an approval asks for an unlimited amount, edit it down to the amount you are actually trading. Wallets let you. Unlimited is how a wallet gets emptied months later, by a contract that looked fine on the day and did not stay that way.
- A bare signature deserves more suspicion than either, not less. It costs no gas, names no amount, and never shows up on the explorer, which is precisely why phishing pages ask for one. It can still sign your tokens away. If you did not expect a signature, do not give one.
- Sign, then open the transaction on Blockscout once. Reading it confirmed with your own eyes is worth the extra click.
the one that matters here
Buying with ETH needs no approval at all. ETH is the chain's own asset, so a straight ETH buy is a single transaction and nothing else. If a page asks you to approve something before your very first buy, stop and read the domain again. You will meet a genuine approval eventually, when you sell the token back or trade it against another ERC-20, and that one is ordinary. The first one is not.
if it fails
A failed transaction does not take your tokens, but it does keep the gas. The chain ran your instructions, hit a condition it did not like, and threw the whole result away while still charging for the attempt. Annoying, cheap, and completely normal. Usually it means slippage was set tighter than the price moved.