Recover iCloud data from lost device My friend had an iPhone 6 that was lost recently. The phone is offline now so we couldn't locate it using Find My Phone

She wants to recover the data from the iCloud account connected to the lost device. When she tried to login to the Online portal for iCloud, we were asked to enter a verification code that was being sent to the lost device. So she got a new sim card under the same number, put it in a new phone and tried the SMS option for the verification code. But it seems any sms that is being sent to the number is sent as an to the lost device and not as a normal sms. So we cannot get the verification code now.

Any other way to get the verification code or possibly change the phone number of the iCloud account without access to the device ?

Thanks in advance.
It sounds like the account is protected with two-factor authentication.
According to the FAQ on Apple's information about two-factor authentication

What if I don’t have access to a trusted device or didn't receive a verification code?
If you're signing in and don’t have a trusted device handy that can display verification codes, you can have a code sent to your trusted phone number via text message or an automated phone call instead. Click Didn't Get a Code on the sign in screen and choose to send a code to your trusted phone number.

You mentioned that the phone number is still the same, however, the normal SMS option is not working, so I would try the phone call method instead.
There is more information about how to get a verification code and sign in with two-factor authentication available at https://support.apple.com/en-us/HT204974.
Should these options still not work, you can request account recovery to regain access to your account.