wrong 3b upload

we are GTA service provider.we don't charge GST in our Invoice.Party deposit GST on our behalf on RCM basis.
In July 2019.we wrongly file GSTR 3B. we upload wrong figure (26600132/-) in 3.1(c) in column on 3b. the actual figure is Rs 6484680/-.

sir what We do?How we rectify