RcM on Rent paid in GST

You have to show the same in Form GSTR 3B table 3.1(d) as inward supplies liable to reverse charge and also show in the table 4(A)(3) for availing the same as input credit. Finally liability will arose against RCM which has to be paid in cash.

I am also facing the same problem. 

If you are availing ITC in Table 4(3) of which decalred in Table 3.1(d), just ignore the error.  As you are making payment of GST liability under reverse charge you are eligible for availing input credit of the same.