Go to Wallet -> Private keys -> Export
Enter your password to get your private keys and matching addresses in plaintext json or csv format.
You said you created a new wallet, was it in the same Electrum?
maybe you're exporting the private keys of the new wallet instead of the old.
To change wallets in Electrum, click the file tab then click open, select a different wallet file from the list, and try again.
Just remember the golden rule when you do this. Once the Private Keys are exported and entered onto some wallet service, then it is regarded by many people to be "exploited" and not to be used again. Even the plaintext json or csv file leave traces on your hard drive, so be prepared to create a new wallet, after you have done this.
Also, those private keys should never be thrown away, because there are many other forked coins that could be extracted from that.