I am a host of a hostel in Thailand and cannot receive any email from WAKA, which is an online travel agent, that can bring me customers from China.

I have checked with WAKA guys to get some details below

• Email address: do-not-reply@globalmail.waka.life
• IPs: 166.78.69.245, 198.61.254.117 
• Email service provider: mailgun.org