I have no reason to doubt Abi99's competence or good intentions, the problem so far seems to be his repeated inability to understand my posts. I don't think I've been at all ambiguous or obscure.
It is OK. It was a misunderstanding. I did not know what you meant with the word ‘section’. Now, I got it. You are looking for a firmware update, downloadable somewhere on the Web offering of Microsoft, Nokia, or HMD. To say it short: Nokia Mobile Phones (and Microsoft Mobile) did not intend to update your phone. Why ever. Therefore, you did not find something like that.
How to track a Nokia mobile phone? Are you worried about your children’s whereabouts? Do you want to know the location of you spouse if he or she is returning home late? Or you may be keen on tracking employee whereabouts especially for important assignments. Whatever be the reason – tracking a Nokia Mobile phone is easy and not complicated.
When it comes to Software security and that advise of shop employee, puh, difficult to answer that in general. Your phone offers several interfaces (GSM, microSD, USB, and SMS). Theoretically, someone could intercept one of those interfaces and do bad things. If there is a software bug. However, no, not a single attack is known for the operating system of your phone Series 30+. At least, I am not aware of any such attacks or security vulnerabilities. However, yes, when a phone model or software platform does not get any security updates, it is questionable whether that phone should be used any further. Microsoft answered that question for you, because your phone does not even allow updates. Whether one believes Microsoft and their decisions is … well, another topic. By the way, Vodafone answered that question as well: They (still) sell the Vodafone Smart platinum 7 (Android 6.0) and that has not received a security update for more than half a year (mine is on 5th of September 2016). Therefore, whether one believes Vodafone and their statements is … well, go figure!
All parties should be more open to that topic. Security vulnerabilities are part of software. They can happen next day, they might not happen ever, they might to flourish in obscurity. It is good that your are aware and look for it. Especially, because Microsoft and Vodafone are not on the right track, yet.