"No default Bond

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I am trying to simulate a cyclic peptide using GROMACS from a name.pdb file.

I ran gmx pdb2gmx -f *name*.pdb -o *name*_processed.gro -ignh with forcefield 6 (AMBER99SB-ILDN protein, nucleic AMBER94 (Lindorff-Larsen et al., Proteins 78, 1950-58, 2010)) and water model 1 (TIP3P).

I then created a box with gmx editconf -f *name*_processed.gro -o *name*_newbox.gro -c -d 2.5 -bt cubic, solvated with gmx solvate -cp *name*_newbox.gro -cs spc216.gro -o *name*_solv.gro -p topol.top, and tried to run gmx grompp -f ions.mdp -c *name*_solv.gro -p topol.top -o ions.tpr -maxwarn 1. Unfortunately, this throws an error that is shown below.

ERROR 1 [file topol.top, line 517]:
  No default Bond types

ERROR 2 [file topol.top, line 2154]:
  No default Angle types

ERROR 3 [file topol.top, line 2157]:
  No default Angle types

ERROR 4 [file topol.top, line 2159]:
  No default Angle types

ERROR 5 [file topol.top, line 2160]:
  No default Angle types

ERROR 6 [file topol.top, line 2958]:
  No default Angle types

ERROR 7 [file topol.top, line 2959]:
  No default Angle types

ERROR 8 [file topol.top, line 2960]:
  No default Angle types

ERROR 9 [file topol.top, line 2979]:
  No default Proper Dih. types

ERROR 10 [file topol.top, line 2980]:
  No default Proper Dih. types

ERROR 11 [file topol.top, line 2981]:
  No default Proper Dih. types

ERROR 12 [file topol.top, line 2982]:
  No default Proper Dih. types

ERROR 13 [file topol.top, line 2983]:
  No default Proper Dih. types

ERROR 14 [file topol.top, line 2984]:
  No default Proper Dih. types

ERROR 15 [file topol.top, line 2985]:
  No default Proper Dih. types

ERROR 16 [file topol.top, line 2986]:
  No default Proper Dih. types

ERROR 17 [file topol.top, line 2987]:
  No default Proper Dih. types

ERROR 18 [file topol.top, line 2988]:
  No default Proper Dih. types

ERROR 19 [file topol.top, line 2989]:
  No default Proper Dih. types

ERROR 20 [file topol.top, line 2990]:
  No default Proper Dih. types

Excluding 3 bonded neighbours molecule type 'Protein_chain_A'
Excluding 2 bonded neighbours molecule type 'SOL'

NOTE 3 [file topol.top, line 4320]:
  System has non-zero total charge: 4.000000
  Total charge should normally be an integer. See
  http://www.gromacs.org/Documentation/Floating_Point_Arithmetic
  for discussion on how close it should be to an integer.
  
WARNING 1 [file topol.top, line 4320]:
  You are using Ewald electrostatics in a system with net charge. This can
  lead to severe artifacts, such as ions moving into regions with low
  dielectric, due to the uniform background charge. We suggest to
  neutralize your system with counter ions, possibly in combination with a
  physiological salt concentration.

How to I resolve this issue?