Can you please give me more details to help you:
- which kind of HCX installation: on-premises to another DC, on-prem to VMC..?
- Did you cautiously follow pre requisites like: unrestricted access to on prem vCenter and ESXi?
- Is there network separation : management port, VMkernel port, network port? With VLAN? vLan routing?
- Do you have enough IP Addresses to deploy HCX vApps as required?