URGENT: 4-month unresolved issue - Requesting formal escalation

I am posting here as a last resort after four months of failed attempts to resolve a lost mobile number issue via standard customer support channels.
Since October, I have repeatedly contacted Lebara via phone chat and email. Despite being promised callbacks, I have received zero contact. This has caused significant distress.
How do I get my issue resolved. How do I raise a escalated complaint.

SanSri Hi SanSri, I can well understand your frustration, I too am replying to your message out of a lack of communication from lebrara.
I have just tried to post an online inquiery from their website and it constantly would not allow me to send. it constantly ask me to describe the problem which I did 10 times and have now given up. I have looked all over the web site for a email address for me to ask about a simple problem but unfortunatly no email seem to exist. I would ask any member of Lebara staff to answer why no email address exist in the contact us section ? I have previously tried to contact by phone, but gave up after an hour when I was cut off
Regards Sad Wilf.

SanSri Hi, thanks for posting.
I'm standing in for Martin who's off for a few days.
For information on how to make a complaint, here's a link to the Lebara complaints code on the website.
I hope that this helps you out.

Marc Thanks Marc

Thank you Marc, on your code of practise page you mention the below before raising it to Ombudsman:
3.3.2 you have been issued a "final position" letter; and.
Did not receive this, after calling the company 3 weeks later I'm told the complaint is closed with no information shared
3.3.3 after eight (8) weeks your complaint remains unresolved
You guys close the complaint without informing the complaintee about it - absurd.
4.3 We'll normally get back to you by phone, if we can't get hold of you, we will send you an SMS. If requested, we can confirm any conversation in writing if you ask us to.
Again never happened. I specifically ask for my complaint numbers and when they were closed and was told this is not something Lebara shares. On my call this week they claimed lebara has no outgoing call facility to its customers, would never call their customers to resolve their complaint.
Can you explain the above points. Is you code of practise ever practised.