Unable to Prevent Spam Registration Osclass Sites

Unable to Prevent Spam Registration Osclass Sites;
Dear friends, please help me, I am getting crazy! as you see attachment, I can not stop spam registrations on Osclass web sites.
What is causing this? I have installed all of osclass spam & captchta plugins. It did not stopped.

Currently I am using Osclass core Spam and bots section. I have added Google captcta code. But still I receive a rainy spam registration ( 200- 300 registrations every day ).

https://www.antalya-dolphinarium.com/user/register normaly as human when you try to register without skipping Captchta answer, site gives error and you can not proceed.
But how I receive those rainy spam registrations than?
What could be reason?
I really want to remove Osclass. Please advice me how I can solve this?

For test propose I have removed " user-register.php " from hosting and it is still registering spam users. I see on dashboard.

How it is possible without user-register.php file those spam bots can register on Osclass site?

@muratbora
Bots will store form information so it is possible to send spam even after removal of file with form.
Use:
1) https://osclasspoint.com/osclass-plugins/protection-and-spam/invisible-recaptcha-plugin_i80
2) https://osclasspoint.com/osclass-plugins/protection-and-spam/anti-spam-and-bot-protection-osclass-plugin_i51