Hey @Miguel_Tejera,
Welcome to the MongoDB Community forums 
I recommend checking if there are any firewall or network restrictions on the Wi-Fi networks where the error occurs. However, it seems like the DNS issue, try using Google’s DNS 8.8.8.8 and 8.8.4.4. Please refer to the Public DNS for more details.
Apart from this, please refer to this response and try using the connection string from the connection modal that includes all three hostnames instead of the SRV record.
If it returns a different error, please share that error message here.
In addition to the above, I would recommend also checking out the Atlas Troubleshoot Connection Issues documentation.
Regards,
Kushagra