Do you know if there is any rule to create a login PIN in OFSC using an SSO connection?

Summary:

Hello OFSC Community;

Do you know if there is any rule regarding the type of characters allowed or length of the string to create a PIN when a user logs into OFSC for the first time using an SSO connection?

Content (required):

The problem that we have is that some users the first time they try to connect, when trying to enter the PIN, OFSC returns the following error:

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The OFSC documentation (https://docs.oracle.com/en/cloud/saas/field-service/faaca/c-aboutsettingpin.html#concept-1-E04B314F) only indicates how to create the PIN and when to use it, but does not detail any considerations regarding which characters are allowed to be used or the length of the pin.