Hello again Freel2 community. Happy new year to you all.

Having recently had a phone upgrade I am trying to pair my phone with the in-car bluetooth.
When I go into the Phone settings menu......Phone Settings, Bluetooth & Phonebook all have a locked padlock symbol next to them. How can I unlock them?
I must have some how done it before to pair my old phone - but can't seem to gain access now.
I seem to remember from last time that I had too delete the previous phone - but can't see away to do it now. All sub menu options show a padlock?
Any ideas?
For the time being ive got it paired with the XTRONS Android Headunit (after market replacement for the LR Sat Nav) but its internal speaker etc is not as good as fully integrated with the rest of the car handsfree system etc.  Current Vehicles:
2007 Freelander 2 - XS Tabora Flame TD4
1989 Range-Rover Vogue SE V8 3.9 Petrol/LPG
1976 Land-Rover SIII SWB 88 County, 2.25l Petrol/LPG
Past vehicles:
1999 Range-Rover P38 V8 4.0 - Money pit
1988 Range-Rover V8 3.9