Hello @Zieppegu10
The 2FA has been set up to increase the security of your data https://tinyurl.com/mwbcbxsm
It is possible to manage the login method of the My Swisscom account and choose to enable the two factor authentication (2FA) only for some actions. in your My Swisscom account under My profile > Manage the login or via our assistance.
For security reason, only a Swiss number is accepted. For customers with a foreign phone number, we suggest to get a prepaid SIM card or to put the number of a family member or a friend.
Hope it helps!