Unable to create same tag with different subinterface

[Rajendranahak]

all wan subnets they have created single vlan id 200 and for all there is a single gateway.
Project 1: wan1: 172.30.20.2/24
Project 2: wan2 : 172.30.20.3/24
.
.
.
Project 7 : wan3 : 172.30.20.7/24

For all project gateway is 172.30.20.1/24 because all subnets assigned to same vlan id.

All projects have assigned in different VR & Vsys.

Checkpoint - L3 Switch- un-managed switch - wan router (Physical Connectivity)

if we create different vlan id for each subnet then there will different gateway for which we need to replace un-managed switch and need to create sub interface in router. Also there will be changes at project side and customer will ask them about changes, so XYZ team don't want to go with this solution.
In checkpoint also they faced same issue. same like PAN NGFW we cannot give same vlan tag for two or more sub-interface in checkpoint. For workaround they have created virtual switch in checkpoint , same solution we are checking in PAN NGFW.
So Please help me over here.

Thanks in advance.

[SutareMayur]

@Rajendranahak  Hello Rajendra, please check below article, if this helps you.

https://knowledgebase.paloaltonetworks.com/KCSArticleDetail?id=kA10g000000ClRqCAK

- Mayur