Quote from: privacyn3on on Today at 12:24:12 AM

Then I opened the client again after some time, it was synced too and then I sent another transaction. But this time, when I go to transactions tab, it shows a "?" symbol next to all the transactions in the past which were confirmed as well and even the newly initiated transaction.

It could mean that your wallet.dat was corrupted or the parent transaction was suddenly became invalid.
It's uncommon that previously confirmed transactions become invalid since they are safely stored in the Blockchain.

Have you force-closed Bitcoin core or had a power-outage while you're using the wallet?
What version of Bitcoin Core are you using?

Quote from: privacyn3on on Today at 12:24:12 AM

What do I do now? The balance has been deducted already from my Wallet but transaction id is not showing up.

It can be removed by right-clicking on it and selecting "Abandon transaction", that will remove it from your wallet.
But that's just a "band-aid solution" since the previous transactions are all invalid.

The RAW transaction from the oldest '?' transaction can shed a light to the issue.
You can get it by right-clicking it and selecting "Copy Raw Transaction", then paste the result here inside [code][/code] tags.
Note: Doing that will share your transaction's inputs and outputs, but that's basically the same as sharing a valid transaction ID that can be explored from a blockexplorer (not good for privacy).