Security code sent to landline phone number

[SkyRavenHK]

I couldn't log onto MyVodafone, and I went to reset password.
I tried to log in after receiving a temp password, but then it only prompt me to receive a "security code" to my landline phone number... by unknown means (SMS?? phone call that reads out the code?? is landline phones even capable of receiving SMS??)
Since I don't have a landline phone handset, I am stuck.
It is not sensible that I have to pay for a landline phone handset just to reset a password,
let alone it is caused by the system not correctly setting my mobile phone number as primary number to receive the stupid security code by SMS, which isn't very secure at the first place.

[Jason]

Hi @SkyRavenHK. It's disappointing to see your post and your concerns regarding our security measures when logging in. If you've got a Vodafone mobile number with us, the security code will be sent to the registered Vodafone number. If you don't and you haven't registered an alternative contact number, your home phone number will be automatically chosen, as there isn't any other number to fall back onto. To both help you get logged back in and to register an alternative contact number, please reach out to our Social Media team. 

[SkyRavenHK]

Thanks for the reply.
Interesting. I don't remember the whole thing exactly but I did have SMS records for the modem/router package and openreach installation reminder, which indicates that I have indeed provided a mobile contact number...
Anyway, thanks for the suggestion and I will try contacting via social media... despite it is pretty much way less "secure" than the "security code via SMS", which isn't very secure at the first place.