Why is Congress troubled by PM CARES fund?

At the beginning of Coronavirus Covid-19 pandemic, PM Modi had launched a PM CARES Fund asking the general public to donate some amount to assist the nation in fight against Covid-19. However, the fund has been constantly attacked by Congress. In his recent press conference, Congress leader Rahul Gandhi demanded an audit on the PM CARES fund. Gandhi also said that record of the expenses from PM CARES fund should be made available to public.