Hello @pink-smurfy sorry to hear you are having problems logging in to MYEE online. Try another device or browser if you can (Firefox seems to be most compatible currently) or clearing the cookies/history of you current browser then trying again.
If none of the above work please call customer service on 150 from your EE phone or 07953 966 250 from any other who can access the account and check/register the number for you. If you are a personal pay monthly customer on an EE plan you can also access Live Chat using one of the ways mentioned in this link. :):