Error about sanitizing data is caused by ModSecurity. ModSecurity is an Application Firewall that filters, monitors, and blocks HTTP traffic to and from a web application. By inspecting HTTP traffic, it can prevent attacks stemming from webion, and security misconfigurations.
Items that are likely to be blocked or cause an error application security flaws, such as SQL injection, cross-site scripting (XSS), file inclusror/conflict are the following:
SRC, Style, !=, <>, /bold. This is not an exhaustive list.
As for the hyperlink, we would advise using any online to shorten URL https://www.shorturl.at/ as a long URL might also cause this issue.
And for copying text from Word, it is better to do formatting in Portal as text in Work might contain whitespace characters and non-Unicode characters. Copying text directly from Word will copy those as well and you might not spot them. So it would be better to type text in Portal.
To Resolve
You would need to determine which paragraph is causing the issue (by copying and pasting it into the portal). Once you know it try typing the words and saving after two or three words.
Sometimes words like 'from' and 'create' can trigger the error - If so, you must update the wording of the text.
If there are URLs then try shortening the URL.