Youtube can't establish a secure connection?

For a few months now I have simply not been able to use YouTube on my laptop at certain times of the day. It then says: This website can't provide a secure connection.

And below that (if that should be helpful): ERR_SSL_PROTOCOL_ERROR

I have already carried out a network diagnosis without any findings. My internet is very good, it can't be that. I don't know what to do and how to fix it. Could anyone help me, please?

Is the date / time correct on the laptop? If the CMOS battery is empty and the times are temporarily incorrect, certificate errors can occur. (just getting into the blue would be a possibility…)