Can only connect to AWS Elastic Beanstalk API on a specific network

Question

I have a .Net API deployed in Elastic Beanstalk which is working over the weekend then suddenly I can only access it when using my “WI-FI connection” but when I use my “LAN or Mobile Data” I cannot reach it even if it has internet service. It is also the case for my other colleagues. Even Postman cannot reach it a “Getaddrinfo EAI_AGAIN” error and browser has "DNS_PROBE_FINISHED_NXDOMAIN"

The API can be access in LAN when using the “Elastic Beanstalk Domain” but cannot be access with the “custom domain” found in SSL/TLS AWS Certificate Manager (ACM) which is link to the port of Load Balancer HTTPS:443. Note that VPC, Load Balancer and Elastic Beanstalk indicates that they are healthy, active and available.

Action before hand:

1. Deployed an API last two days

See images below:

Current Actions done:

1. Update Platform from IIS 10.0 running on 64bit Windows Server 2016/2.12.0 to IIS 10.0 running on 64bit Windows Server 2016/2.13.2
2. Refreshed Elastic Beanstalk
3. Saved Current Configuration
4. Revert to old API Builds

Using LAN I have the following troubleshooting result:

Ping command result
Request timeout for icmp_seq 0
Request timeout for icmp_seq 1
Request timeout for icmp_seq 2
Request timeout for icmp_seq 3
Request timeout for icmp_seq 4
Request timeout for icmp_seq 5
Request timeout for icmp_seq 6

Netcat result

nc -v <elb_ip_address> 443
Connection to <elb_ip_address> port 443 [tcp/https] succeeded!

traceroute shows successful routing up to Amazon's network, suggesting that your request is reaching Amazon's infrastructure.

curl: (6) Could not resolve host: <custom_domain>

What command can I do to troubleshoot further or what could be the root cause and solution for this issue?