Almost always a payment that has not finished confirming, not money that has disappeared. Banks show a charge the moment it is authorised, which can be minutes before the order appears.
Check these, in order
1. Your orders. If it is there and says the payment is pending, nothing is wrong yet — it is still settling. My payment is pending
2. The amount. A held or authorised amount is not always a completed charge, and your bank may describe both the same way.
3. Whether you were signed into the right account. One verified number belongs to one account, and an order lands on the account that paid. Can I have two accounts?
4. Whether the payment failed at the end. A failed payment can still show a temporary charge, which is released by the bank rather than refunded by anyone. My payment failed
When to raise it
If there is no order after a few hours, raise it from Help under Orders & payments with the time, the amount and your bank's reference.
Do not wait a week. Early is easier to trace, for everyone.
What not to do
Do not pay again. The commonest expensive mistake on this page. If the first payment did complete you now have two, and sorting that out takes longer than waiting did.
Do not go to your bank first. A chargeback is weeks rather than days, it does not pause anything, and here there is a faster route with the money still inside the system. What is a chargeback?
Do not pay a seller directly to "sort it out". That is outside every protection on this site.
If you won an auction and the payment is stuck
Say so quickly, because the payment window is 30 minutes and an unpaid win counts as a strike. A payment genuinely in progress is not the same as not paying, and it is far easier to explain while it is happening than afterwards. What is an unpaid win?
What a real charge looks like
A completed order appears in your orders with the item, the price and the delivery. If there is an order, you are fine — the rest is just the bank catching up.
More: my payment is pending, my payment failed, is it safe to pay on Metzee.