You have a MultiSig wallet... so as the name suggests, it requires multiple signatures to be able to send transactions.
When you originally set up the wallet, it would have asked you to enter the keys for the "cosigners". So you need to sign it with your wallet (1 signature)... and then save the transaction and open it in one of the other 2 consigner wallets... and then sign it with one of them... and then you'll have the 2 signatures required and the transaction can be broadcast.
Do you have an icon like this on your main wallet window? If so, then you have a 2FA wallet... and you can restore it in such a way that 2 of the 3 keys will be on your computer so you can sign it automatically with 2 keys.
![](https://ip.bitcointalk.org/?u=https%3A%2F%2Ftalkimg.com%2Fimages%2F2023%2F11%2F15%2Fzqndb.png&t=665&c=39alrd1UhzFnHw)
If you don't have that icon, it is just a normal MultiSig... and without the other private keys, you won't be able to sign.
![Undecided](https://bitcointalk.org/Smileys/default/undecided.gif)
Also, it looks like you're using 2.6.4? That is a very OLD version of Electrum... you might want to consider updating at some point
![Wink](https://bitcointalk.org/Smileys/default/wink.gif)