Your issue is very straightforward—you don’t actually have enough usable balance to buy anything.

From your screenshot (on Spot trading):

Available balance: 0.00000361 USDT

Max Buy: 0 NIGHT

That amount is essentially zero in trading terms. Even the cheapest order on the NIGHT/USDT pair needs a minimum value (usually around 5–10 USDT on Binance).

Why the Buy button isn’t working

Your balance is too small to meet the minimum order size

So Binance disables the trade → shows Max Buy = 0

How to fix it ✅

You need to add more USDT to your Spot Wallet:

Option 1: Transfer (if you already have funds)

Go to Wallet → Funding / Futures / Earn

Tap Transfer

Move USDT → Spot Wallet

Option 2: Deposit

Tap Deposit

Choose USDT

Send from another wallet/exchange

Option 3: Buy USDT

Use P2P or card purchase inside Binance

Important tip ⚠️

Even if you add a small amount like 1 USDT, it still may not work due to minimum trade limits. Aim for:

At least 5–10 USDT to trade comfortably

If you want, I can guide you step-by-step based on what you currently have (P2P, bank, Easypaisa, JazzCash, etc.).