The Login information stated in the invitation e-mail "Welcome to Teachme Biz!" does not have an Expiration Date.
You can continue to use it as-is even after time has passed.
※The e-mail will not be sent in the following cases:
- No E-Mail Address was registered at the time of the invitation
- Registration was completed using the CSV batch registration feature without checking "An e-mail is sent to added users after registration is complete."
If you are unable to log in with the stated information, the following possibilities may apply.
- The Group ID has been changed
- The Account name has been changed
- The Password has been changed
- The user has been deleted or suspended
Related: I cannot log in. What should I do?
https://help.teachme.jp/hc/en-us/articles/900005507706