Start with the following 5 steps

 

1. SENT the following message.

Copy & paste the following enclosed message below - this is your last message to the scammer to let her / him / them know that they are guilty for abusing your trust and blackmailing you

Sharing my pics, video or messages to you is not a criminal offence, but you BLACKMAILING me (sextortion) to send, publish or distribute any of our privately shared information, pictures or video WITHOUT MY CONSENT is a criminal offence! Local Police will be interested in offenders distributing child (up to 18 years of age) pornography!
It is illegal to post THREATENING, INTIMIDATING or HARASSING content and or messages on WhatsApp, Facebook or Instagram! (see their T & C’s) and I’m reporting your number.
I’ve made sufficient copies of your online stats to file a proper case with a cyber-criminal offence prosecutor and I have contacted a trusted person to help me deal with this situation you have placed me in.

2. STOP all further communicating.

don’t wait for them to reply or be curious about their next move, you need to get out of the trap

3. TAKE screenshots of messages, profile names and numbers used.

you might be able to report it anonymously online depending such services in your country

4. REPORT & BLOCK the person on the relevant media platforms.

5. TALK to a trusted person and / or get professional help.

in addition to legal assistance get some trauma counselling. This can be traumatic and you will need all the support as possible