This is a “void” property, which means that it is immediately available. These are uploaded by landlords and there should be a link in the message which will take you to the advert for that home. Here you should find instructions on how to bid for it (most landlords give a phone number and/or email address).
If this isn’t appearing any more, it could be because the home has been taken down. Some landlords will only advertise these for a very short space of time (in some cases less than a day).
For further information about one of these properties, you would need to contact the landlord in question directly.