Nginx ingress controller upgrade via helm chart

Hello all,

I was working on upgrade of nginx ingress controller helm chart in eks. Currently we were having 1.15.0 chart version of nginx ingress controller now we need to jump to 3.34.0 which is basically a huge jump . My point is that , in the nginx ingress controller yaml , their is one yaml for creating service of type load balancer , but when i was trying to upgrade that service , it is getting removed and then created , but while creating it is spawning a new new (network load balancer) instead of using the old one,

Can anyone help me to reach to the point where the service can delete and recreate but the aws nlb it should use the existing one.