SARS POOR SERVICE AND SILENCE

my company UNHU aluminium is a registered company conducting business in Johannesburg. The company currently imports from China and distributes aluminium extrusions locally. When the goods arrive in the country my clearing agents pay the duty and vat on my behalf to SARS and during my vat submission i claim the customs vat back depending on the amount of containers imported. Every vat submission i struggle to get my refund, i have to phone SARS frequently , SARS even dont stick to the rule of 21 working days. SARS is killing my business and cash flow is very important in any business. How am i gonna survive in business if SARS conducts itself in such a poor manner for a government institute that was suppose to be at the service of local businesses. due to the delays of non payment from SARS i have no been able to pay my suppliers and even defaulted on payments. SARS has destroyed my credibility with suppliers. When i submit my vat return my submission gets chosen for verification, i submit the documents required within 7 working days and then i never hear from SARS again. My accountants must call SARS, escalate the issue, log a complaint on E-filing and wait. SARS does not even care to respond at all., just dead silence. i have totally lost respect for this institution. Many businesses will close doors to the poor service provided by SARS. i hope someone can assist me with my problem, my workers jobs are at stake.