Losing connection Intermittently CAX80

Update: The ISP tech tested the line until there was no interference and packet loss. He changed all the end coaxial connections. I mentioned to him the logs but he did not know what those were at all. I contacted Netgear support and they identified one of my upstream channels out of range. Netgear support told me to get my ISP to get all the channels into range. Once I do that and there still is a problem they told me to contact them again. After the ISP tech left there was still the problem of slow Internet connection. I paid for 500mbp download and I am constantly getting 150mbp download. I am not sure if it has anything to do with it but the cable that comes into my house is CAT6 and there is a small portion of the cable which is more that 15 years old which is means it is probably CAT5 (and it is the older double cable). It is CAT6 going directly into my cable modem/router.