If your business’s main purpose is to supply labour, and somebody else or another business is involved in managing the arrangements for your business, please read this article:

https://www.gov.uk/government/publications/spotlight-32-managed-service-company-legislation-tax-avoidance-scheme-involving-unpaid-paye-and-class-1-national-insurance-contributions/spotlight-32-managed-service-company-legislation-tax-avoidance-scheme-involving-unpaid-paye-and-class-1-national-insurance-contributions#_blank 

If your business is a MSC, certain payments your business makes to its workers which are not earnings, like share dividends and loans, are treated as earnings, and you will be asked to pay PAYE income tax, Class 1 National Insurance contributions (NICs), interest and penalties (if appropriate) on those earnings.
If there is tax and NICs due on payments treated as earnings, and it cannot be recovered from your business, unpaid amounts will be transferred to certain persons which includes your directors, the MSC provider and their directors.