When you reset your passphrase without a recovery key, new encryption keys will be generated, and you lose access to your contacts and groups.
Your existing contacts will be informed that you have re-set your passphrase and your keys, and must re-confirm you as a contact.
This is partially a security measure to avoid account fraud. It is also a result of the technical design of the cryptographic key exchange:
Since Crypho does not have access to your cryptographic keys, there is also no way for us to accesss your existing content. Since we cannot see it, we also cannot give you access to it.
In order to avoid losing access to your groups when resetting your passphrase, make sure to create a recovery key.