Gstr 3b payment query

we have filled Gstr1 properly and we had done all payment of Gstr3b upto march 18, in July to sept month we had done Gstr3b payment including interest. and same amount stand in cash ledger, whenever we have filled April. Gstr3b , cash ledger amount adjusted through Portal and less amount paym ent had done, now we have to file Gstr3b may 18, and as per our knowledge we have not paid any excess but due to cash ledger adj.less amt paid to GST portal, now how can we solve our Gstr3b problem