My site was is attacked by spam through ContactUS form and subscribtion form

I don´t think so, i use default  https://eqterm.pt/contactus

Setup / enable Captcha.
The settings are on the General Setting page.
https://admin-demo.nopcommerce.com/Admin/Setting/GeneralCommon

Just ad new field in the contact form. Best option will be Country field.  
I was facing too much problem with spam "new account" registration. Tried google CAPTCHA, blocked thousands of  IP, Block countries  but didn't work out.

After adding the country field in the registration form problem has been solved.

manwarhossen wrote:
Please elaborate.  How does adding the Country field "block"?  (Is it because it's a required field?  I suspect the spammers will eventually populate it ;)

New York wrote:

Sorry for late reply. Sorry, I didn't received any notification.
please go : Admin/Setting/Customer Setting
in the Customer form fields please enable as bellows:
'Country' enabled
'Country' required


I had too much issues with spam registrations. Fortunately after adding the country field enable & required problem solved permanently.

Try this plugin
https://www.foxnetsoft.com/nopantibot

Today we have successfully addressed the challenges associated with reCaptcha for our Contact Us and Registration forms. Our approach involved the utilization of stored procedures to scrutinize and eliminate any records suspected of being inauthentic.

For the Contact Us form, this method has proven effective in identifying and removing questionable entries directly through database operations. Similarly, the registration process has been fortified by imposing strict validations on required fields, thereby preventing the dispatch of emails from unauthorized sources.

These measures have significantly enhanced the security and integrity of our user interactions, ensuring that only legitimate requests and registrations are processed. I believe this development will contribute positively to our operational efficiency and user experience.

Should you have any questions or require further details on the implemented solution, please feel free to reach out.

Best regards,
Dario

Pleas share with community what you did and if possible you can share the stored procedures as well.
I am still using stored procedures for my store.

Thanks,
Sateesh M

FYI... In the past, I mentioned how I used a Trigger to deal with spam contacts.