If the bottom of the main window of your Bictoincore.org wallet looks like this, you need to wait for it to catch up (it is still busy downloading details of recent transactions)
The icon at bottom right (two arrows moving in a circle) indicates the wallet is busy "catching up".
What wallets really contain
Remember that wallets don't actually contain money and don't really receive money. They provide a view of the public blockchain - a list of completed transactions that every wallet either creates its own copy of, or in the case of other types of wallet (SPV etc) has access to some other way. If the blockchain data says you have received the money, you have received it. Regardless of what your wallet says.
The only important data in any wallet is a secret number called a "private key".
The public blockchain is the only truth
As you know, when I write "blockchain", I mean the concept, not any of the many unrelated businesses who subsequently used that word opportunistically as their name or part of their name. I suspect their use of this name can confuse people.
There are many public websites that offer a view of the blockchain. By checking a transaction-id or address in several of these you can find out whether you have received money - regardless of what your wallet says. You don't need a wallet to receive money in Bitcoin. You only really need a wallet when the time comes to spend money in Bitcoin. Including when you use it to purchase other currency.
Checking whether a transaction is complete
A randomly chosen blockchain explorer says
2020-07-07 19:45 Block 638188 1711 confirmations
10.73060786 BTC bc1q7⋯zpemf 38Un8⋯7YWqm 0.00279737 BTC
13bVn⋯gxQig 0.01100000 BTC Unspent
1AKWv⋯rAvB6 0.01260000 BTC Unspent
1JAE7⋯W5sDP 0.03600000 BTC
3BMEX⋯f958k 0.23655533 BTC
bc1q7⋯zpemf 10.43155304 BTC
(I shortened the addresses to make the table fit here)
So 0.0126 BTC has definitely been received by the owner(s) of whatever wallet(s) contain the private-key from which was derived address 1AKWvdsoAQC43sBANr9pCnk74nHCdrAvB6
If your wallet doesn't show this, there can be several causes
- Your wallet is not fully synced as far as block 638188
- You don't in fact have the private-key from which that address was ultimately derived.
- Something else.
Checking whether a Bitcoin Core wallet knows about a transaction
In Bitcoin core it is usually obvious if the wallet has not finished synchronisation. You will see a message like this:
If not you can check from the "Debug Window" in the "Help" menu
Then you can click the "console" tab and then type command
getblockcount at the bottom
Here we see this wallet has only retrieved blocks as far as 554269
Therefore this wallet would not know about your transaction in block 638188.