Magento 2 stops responding when sending a form email

[infofontel0a48]

I recently set up my Magento 2 (2.4.3) website and it's working almost perfectly well. However, I ran into a new issue today. After installing an extension for custom forms, my website stops responding whenever I submit the form. The only way to make it work again is by doing

sudo reboot

It's weird because my transactional emails work without any problems. I am using the SMTP plugin by Mageplaza and this is my custom forms plugin.. I contacted the developers already, but I'd like to see if someone could help me now.

I cannot post any logs since there are no unusual logs in /var/log directory. I'm really confused!

[Mukesh Tiwari]

Hi @infofontel0a48 

Please check the following logs also.

/var/log/apache/error.log (If you are using Apache2)

/var/log/nginx/error.log (If your are using Nginx)

/va/log/mail.log

What do you mean by site stops responding? It hangs or frontend is broken?