Contact Us form showing success message but not sending emails

Hi, on my shopify store I have contact us form here https://suitrepublic.ie/pages/contact-us

after filling our the form fields and submit it shows success message but not sending emails..

I tried with verification of from email with domain A records

I tried with changing to email to my gmail email also just in case if its bounces back but no luck

I tried with shopify support but they are unable to fix this issue and just asked me to try to get help from shopify community.

Can any one guide me how I can make this form emails working…Thanks