While this is technically possible, it is not a supported behaviour.
After being activated, AuthAnvil tokens act as a standalone device with no wireless communication. They generate their own list of codes in sequence, and the server software generates codes to match. Each time you press the "Get Password" button, the next OTP (One Time Password) is generated on screen.
If you activate the same single SoftToken on two separate devices, both devices would generate the same list of one-time passwords, but one of the two devices could be generating a OTP that had already been used by the other token. This requires extensive management and tracking of the OTPs, leading to the system very quickly becoming unstable.
If you want to use two different devices as tokens, our recommendation is to assign two tokens to the user. Instructions on doing so are available in this knowledge base article: Can two tokens be assigned to a single user?