errors on submit form URI, AWS ubuntu

I succeed in showing my main mage : http://ec2-54-180-124-114.ap-northeast-2.compute.amazonaws.com/

but on my sending form job, It brings error POST http://ec2-54-180-124-114.ap-northeast-2.compute.amazonaws.com/comments 404 (Not Found)

php artisan route:list is showing routes fine, and my local homestead is working fine. I can't figure it out. is it db -connection error? or route error? or gmail-connection error on my controller@store ? I'm new on webserver hosting. give some advices please !

via Chebli Mohamed