Azure Virtual Firewall (NVA) - Query around PAT and NAT

Hi guys We recently deployed some fortigate NVAs in our Azure environment. We have used the templates in the Fortigate GitHub repository, The configuration we went with was Active-Active, using an internal and external Azure load balancer, so being in an LB sandwich. We’ve been struggling to figure out how to perform NAT and PAT whilst being in this configuration. Can someone with the same configuration please share detail around how to achieve this? It’s been driving me mad!