Method 1

Open the debug console and enter the following commands:

restoreaddresses 100
rescanblockchain

If your address is still missing please check this more detailed guide: https://veil.freshdesk.com/support/solutions/articles/43000472093-how-to-correctly-restore-wallet-from-seed-words-or-find-lost-veil

Method 2

1. Find the address you are missing and copy the address.

2. Open the debug console and enter the following command:

getaddressinfo <address>

3. Find the line ismine and it should say true, if it says false you might have restored from an incorrect seed or copied an incorrect address. If ismine : true go to step 4

4. Input commands:

dumpprivkey <address>
importprivkey <outputfromdumpprivkey> <oldaddress>

All commands should be without the < >