MPS here are the codes that I collected for the Nokia phone? Why would your carrier not allow you to update? Anyhow looks like you might just have to contact your carrier to see if it is a sim card issue.
Basic Reset or Soft Reset for nokia 6086
This option restores the .ini files from the ROM.
Does not erase data (photos, videos, documents) or applications from
a third party. Key Code *# 7780 # (click this combination of keys on the
keyboard in the mobile)
Total Reset or Hard Reset for nokia 6086
This option restores the original operating system from the ROM.
Formats the C: partition and deletes all data including the memory
card. Key Code *#7370# (click this combination of keys on the keyboard
in the mobile)
Important: To proceed to reset, the battery must be full and the
mobile device connected to the charger. If during the course of reset,
the mobile stop receiving electricity it can ruin the internal flash
memory of the mobile device and stop function.
*#06# for checking the IMEI (International Mobile Equipment Identity).
*#7780# reset to factory settings.
*#67705646# This will clear the LCD display(operator logo).
*#0000# To view software version.
*#2820# Bluetooth device address.
*#746025625# Sim clock allowed status.
*#62209526# - Display the MAC address of the WLAN adapter. This is available only in the newer devices that supports WLAN like N80
#pw+1234567890+1# Shows if sim have restrictions.
*#92702689# - takes you to a secret menu where you may find some of the information below:
1. Displays Serial Number.
2. Displays the Month and Year of Manufacture
3. Displays (if there) the date where the phone was purchased (MMYY)
4. Displays the date of the last repair - if found (0000)
5. Shows life timer of phone (time passes since last start)
*#3370# - Enhanced Full Rate Codec (EFR) activation. Increase signal strength, better signal reception. It also help if u want to use GPRS and the service is not responding or too slow. Phone battery will drain faster though.
*#3370* - (EFR) deactivation. Phone will automatically restart. Increase battery life by 30% because phone receives less signal from network.
*#4720# - Half Rate Codec activation.
*#4720* - Half Rate Codec deactivation. The phone will automatically restart
If you forgot wallet code for Nokia S60 phone, use this code reset: *#7370925538#
Note, your data in the wallet will be erased. Phone will ask you the lock code. Default lock code is: 12345
Press *#3925538# to delete the contents and code of wallet.
*#7328748263373738# resets security code.
Default security code is 12345
Unlock service provider: Insert sim, turn phone on and press vol up(arrow keys) for 3 seconds, should say pin code. Press C,then press * message should flash, press * again and 04*pin*pin*pin#
http://www.ehow.com/list_7710907_nokia-6086-secrets.html
Any chance that you could connect it to your PC and clear the memory with the Nokia software?
http://www.howardforums.com/showthread.php/1539776-6086-Factory-Reset-does-not-fully-perform-factory-reset-how-can-i-fix-this
hope that this helps you out a little bit but at this time it looks like you do not have much of a choice.