Contact form issues

Dear,

I’m using your template game addict for quite some time already.
I recently decided to add a contact form, but I have some issues with it.

I had to put my website in maitenance because there were too much bots spamming me.
I’ve tried adding secure captcha via different plugins, but no plugin works on the contact form.

Could anybody give me some info, or help on how to do it?