Please help me out from this error, furthermore it was working fine before couple of days.
So, I've searched for the error on the Internet, and here's what I found.
EAI_AGAIN means the DNS server replied that it cannot currently fulfill the request
In addition, I used the BitPay BCH testnet explorer yesterday, the previous day, and the previous day. The last three days except today, the server was down and I saw "CloudFlare server down" message on the explorer's page. So, I guess they are moving the IP address behind CloudFlare's proxy, and the transition is not perfect.
Summary: It's not your mistake, but you could try flushing DNS cache.