FINGER PRINT ISSUE WHEN CONNECTING TO MULTIPLE SSH/SFTP SERVERS USING F5

We recently deployed SFTP servers running on three servers and we used F5 to load balance the traffic between these servers. our SAP Servers connects to SFTP servers using F5 VIP to download files automatically. When connecting initially to the SFTP from SAP we receive a message showing the fingerprint of the the SFTP Servers and after accepting, the connection works fine. However after sometime, we face issue saying the finger print is invalid, this is because the connection might hit another server from the pool which has different fingerprint. Our app can only pass one finger print for a single connection. how can we resolve this issue?