Email says I will be charged monthly for the IP's I purchased

I just received an email saying that from December I would be charged a monthly fee for the IP's that I have already purchased from OVH.

I assume there is some error here as I have already purchased the IP addresses from OVH, they are not "rented" monthly.

Is OVH going back on the sale of the IP addresses to me and now expecting me to rent them again?