Betfair have made the following statement:-
Betfair Customer Services 26 Feb 10:14
We are experiencing a technical issue with our international exchange, where some international customers are experiencing difficulties retrieving their P&L during busy periods.
This is the same problem that is also causing some international API customers to experience a “bet in progress” error during busy periods. Betfair Technology teams are working to resolve the issue, and are hoping to have it fixed by the weekend.
We would like to apologise for any inconvenience caused.