对SMIC的PAD的LVS问题

对SMIC18的PAD单独做LVS，报告如下错误，
一点头绪没有，请教可能的原因，万分谢谢！
INCORRECT NETS
1    Net VDD33                                                 VDD33
       --------------------------                                --------------------------
      
       ** missing connection **                                  (_smp2b):out2
                                                                   M193:s
      
      
       ** missing connection **                                  (_smp2b):out2
                                                                   M231:s
      
      
       ** missing connection **                                  (_smp2v):out2
                                                                   M149:b
                                                                   M131:b
                                                                   M131:s
      
      
       ** missing connection **                                  (_invv):sup1
                                                                   M224:b
                                                                   M224:s
      
      
       ** missing connection **                                  (_invv):sup1
                                                                   M174:b
                                                                   M174:s
      
      
       ** missing connection **                                  M238:g
       ** missing connection **                                  M237:g
       ** missing connection **                                  M210:b
       ** missing connection **                                  M210:s
       ** missing connection **                                  M209:b
       ** missing connection **                                  M209:d
。。。。
2）
DETAILED INSTANCE CONNECTIONS
      M2(2.310,114.340)  MN(N33)                      M104  MN(N33)
         g: VDD33                                       g: VDD33
         s: 16                                          d: NET_20
         d: 9                                          ** missing net **
         b: 9                                          ** missing net **
         ** VSSD **                                     s: VSSD
         ** VSSD **                                     b: VSSD
--------------------------------------------------------------------------------------------------------------
       M50(46.550,192.450)  MN(N33)               M69  MN(N33)
         s: 13                                    s: NET_79
         d: 14                                    d: NET_81
         b: VSS                                   b: VSS
         g: 6                                   ** missing net **
         ** VDD33 **                              g: VDD33