These are transient or, more commonly, temporary phone numbers. This indicates that they are only accessible for a limited time. Some phone lines are active for several months while others are only active for a short while. Please refrain from texting sensitive information, such as passwords or private messages to pals, or using a temporary number for website phone verification. The text messages sent to these phone numbers could be accessed by anyone, giving them access to your account. There is typically a maximum number of times you can use a phone number on websites that demand phone number verification. In this situation, it is possible that certain of our phone numbers will be restricted. However, this is not a serious issue.