The Right to Remain Toolkit
This is the best non-government source of information for people seeking asylum who need to understand the UK asylum claims and appeals system.
You can read the information in your own language.

MIGRANT HELP
Those seeking asylum in the UK must come to us to apply for accommodation and financial support, to report issues with asylum accommodation, or to report changes in your circumstances, or to ask for help with problems concerning your Aspen card.
https://www.migranthelpuk.org/
Email: ascorrespondence@migranthelpuk.org
Telephone: 0808 8010 503
UNHCR

The UNHCR page with question and answers about refugees and asylum seekers.
https://www.unhcr.org/uk/publications/brochures/3b779dfe2/protecting-refugees-questions-answers.html