Hi,
I have found Lease Advice Service really helpful. Their website is really useful with case studies & points of law for leaseholders. They also have a phone service where you can call a trained solicitor to discuss your issue in more detail, see attached link:
‘https://www.lease-advice.org/about-us/’
‘https://www.lease-advice.org/advice/’
I hope all works out for you – all the best!