How to set 901 voice mail to give caller number and date / time

[Geoffa]

I have an offensive call on 901 - but the service does not give either  - so how can I get that ? or change some settings so that I can get that ? the date/time or the caller number.  I had cleared the caller list before I found the offensive message on 901.

[MI5]

@Geoffa 

https://www.o2.co.uk/help/safety-and-security/unwanted-calls-and-messages

You need to contact O2.
All numbers are in this guide Guide: Coronavirus Community Help and Support 
When you call, you will be asked for the reason you are calling.
Stay silent for 15 seconds and you will be taken to the keypad options.
Press 2 for Everything Else
Press 5 for More Options
Press 7 for Anything Else which will put you though to someone.
You can also try saying "Upgrade" or "Fraud" to be connected to an advisor.
8.00am is the best time to call if you can.
Also try 0800 977 7793

[madasaf1sh]

@Geoffa

In the Voicemail Menu, you should be able to get the number and date and time, its called the message envelope and option 8.

If the number is withheld no one will be able to get the number that called you.