Steps I have taken AFTER trying software fixes, and reading help-topics around the net. NONE have worked thus far listed below.
Side NOTE; I opened my account in the UK, but we moved to the Far East years ago now. Tried fixes related to that a thousand times.
Ubisoft also hint that some part of my account may be linked, but it is not linking. EPIC tell me that there is No link whatsoever, and my Online Account here at Ubi tells me there is no link to EPIC.
Steps taken; over the year or more.
1) Renewed my graphics card from 1070 to 2060.
2) Renewed my CPU from 4770 to 4790k.
3) Renewed my motherboard from Sabertooth Z87 to RoG Hero Z87.
4) Went from Spinning Drive to SSD.
5) Went from Windows 8 to Windows 8.1.
6) Went from Windows 8.1 to Windows 10.
7) Fresh installs (rather than cloning & upgrading); still no link.
Originally had tried linking for AC Creed Syndicate; then tried For Honor for a year, but no LINK at the Ubisoft side.
9) Bought AC Creed Valhalla Ultimate from EPIC, and tried that a thousand times. Ubisoft stop the LINK.
10) Provided all the details I could remember from the past 10 years about my account, and Ubisoft STILL refuse to permit the link; &/or refuse to tell me exactly what the problem is.
11) Must have tried 52,000 attempts by now etc...
12) Upgraded to 5700X Ryzen CPU with X570S Mo-bo & RTX3080 & Windows 10 onto 4X4 M.2 etc...
... etc
...
..
x) Went back and asked Ubisoft help to assist, but they are not helping, and have just stopped answering my request for them to fix it after EPIC stated they only are preventing the link.
XI) Trying here.