and since I put the domain my wordpress administrator stopped working:
I think it’s because I put it on cloudfare,
Everything works fine for me except access to the wordpress administrator does not let me enter, I deleted the cookies: it tells me that:
This problem is sometimes caused by disabling or refusing to receive cookies.
Sounds to me like an HTTP(S) issue if it’s related to the cookies
However, maybe the web browser cache has to do something in between with it.
Before moving to Cloudflare, was your Website working over HTTPS connection?
I suggest you use the “Pause Cloudflare on Site” option from the Overview tab for your domain at dash.cloudflare.com. The link is in the lower right corner of that page. Give it five minutes to take effect, then make sure site is working as expected with HTTPS. Only then should you un-pause Cloudflare and double-check your SSL/TLS setting to make sure it’s Full (Strict).