There are some possible causes if you can't login to your account.
Pattern 1: Registration procedure has not been completed
To complete your registration, please click the URL in the body of the email with the following subject sent by the inviter, and create a password.
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Title： [ILS] Invitation to ILS（ILS参加登録メールアドレスの認証のお願い）
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Pattern 2: You have entered your email address or password incorrectly.
Does the email address you entered contains uppercase letters, or are there any unnecessary spaces before or after it?
If you forgot your password, please reset your password from the following link.
https://app.ils.tokyo/users/password/new
Pattern 3: Trying to log in with an unregistered email address
You cannot log in with an ILS account that was held before last year.
ILS2025 account registration is required.