Hi there and welcome
This is 100% a scam. This person was not working for TalkTalk and TalkTalk would never call you for no reason.
This is what is known as "phone phishing" it is can be a very serious problem if you do let them access your computer.
Basically what they will do is call a lot of phone numbers and say that you have problems. Any actual computer problems you have will be entirely coincidental. Usually what they will do is show you the windows error log which always shows a lot of errors but these are normal and on all computers, they are not viruses.
Next they log onto your computer and lie to you about the numerous problems they pretend to find. Next they will attempt to get you to pay a few hundred dollars to "fix" the issues when in fact they actually do nothing too helpful.
Always remember, no legitimate tech support company would ever call you. Your router does not report to TalkTalk or any other company so if any tech support person calls you can trust it is a scam and just hang up.
Please do me a favor and take a moment to rate my service by clicking the stars above, 3 or more is very appreciated, we can still chat after rating if you need more help.
ok, well I can assure you Ian I am not tricking you in any way.... so a little concerned you feel this is what I have done to you.
In all honesty I helped you avoid being scammed, and am a little dissapointed you think I have tricked you in some way.... that's not something I am ever told here.. and not how most of my customers would reactive.
It is a pity
If you would like any additional information or assistance, please do not hesitate to let me know.
And if you can take a second to rate my service by clicking one of the stars at the top of the screen then submit, that would be greatly appreciated.