From your screenshot, the issue is very clear:

👉 Your available balance is almost zero

Avbl: 0.0000036 USDT

Max Buy: 0 NIGHT

That’s why the “Buy NIGHT” button isn’t working.

✅ Why this is happening

You’re trying to buy NIGHT/USDT, but:

You don’t have enough USDT in your Spot wallet

The amount is too small even to cover minimum order + fees

💡 How to fix it

Option 1: Add USDT

Go to Wallet → Deposit

Deposit at least 5–10 USDT (recommended minimum)

Option 2: Transfer funds

If you already have funds:

Go to Wallet → Transfer

Move USDT from:

Funding wallet → Spot wallet

Futures wallet → Spot wallet

Option 3: Convert small balances

Use Convert feature to turn other coins into USDT

⚠️ Important

Binance has a minimum trade requirement (usually around 5 USDT)

Your current balance (0.0000036 USDT) is far below that

✔️ After fixing

Once you have enough USDT:

Enter amount

Choose Market or Limit

Tap Buy NIGHT

If you want, I can guide you step-by-step to deposit or convert funds 👍