SARS EFILING BAD COMMUNICATION

SARS out of the blue requested payment of R2500 from me. No statement, letters, nothing! I've tried for several weeks now to register on Efiling. Loaded my personal documents like i/d, bank statements etc as requested. Still Sars want me to phone them. After several times I gave up. Holding for on for 20 - 30 mins and then call is cut off. Eventually I wrote a letter. The reply I got came from Interfront with Sars references requesting again my personal documents. My mail supplier warned said it is a Spam! With all the internet ***** I am not supplying my personal info to a third party. In the meantime Sars threat me with summons. What now??? Can someone help me please. My Sars *** CB Swart.