Upgrading from old equip to x1 DVR and 4 boxes Comcast can’t get boxes to woek

Help please!  We spent over five hours and three phone calls yesterday with Comcast and our boxes that connect to the replacement X one DVR just won't work. There are no problems with our house or cable or anything like that it's just a new equipment.  The new DVR works but the boxes keep getting an error to tighten the coaxial cable and that's not the problem but we keep getting it. Comcast has resent Signal several times but to no avail. Any help would be much appreciated!! It's so bad we're thinking about going back to our old equipment. Which we don't want to do because it cost a whole lot more money. We can't have a technician come out due to Covid risk in our home.