It sounds very American but the "Office of Financial Sanctions Implementation" is a part of the UK Treasury, effectively the equivalent of the USA's Office of Foreign Assets Control, OFSI as against OFAC, then. OFSI is gaining increased attention since the UK left the EU, as the UK begins to develop its own financial sanctions regime.
This case is brought under EU-era law. Importantly, it is also against a FinTech company, a sector widely considered under-regulated and lacking in compliance structures.