Error while generating ION.tpr for a two peptide system

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GROMACS version:2023.5

Command line:
gmx grompp -f ions.mdp -c box_sol.gro -p topol.top -o ION.tpr

Ignoring obsolete mdp entry ‘title’
Ignoring obsolete mdp entry ‘ns_type’

NOTE 1 [file ions.mdp]:
With Verlet lists the optimal nstlist is >= 10, with GPUs >= 20. Note
that with the Verlet scheme, nstlist has no effect on the accuracy of
your simulation.

Setting the LD random seed to -1208009731

ERROR 1 [file forcefield.itp, line 1]:
Incorrect number of atomtypes for dihedral (0 instead of 2 or 4)

ERROR 2 [file forcefield.itp, line 2]:
Incorrect number of atomtypes for dihedral (4 instead of 2 or 4)

ERROR 3 [file forcefield.itp, line 3]:
Incorrect number of atomtypes for dihedral (4 instead of 2 or 4)

ERROR 4 [file forcefield.itp, line 4]:
Incorrect number of atomtypes for dihedral (4 instead of 2 or 4)

ERROR 5 [file forcefield.itp, line 5]:
Incorrect number of atomtypes for dihedral (4 instead of 2 or 4)

ERROR 6 [file forcefield.itp, line 6]:
Incorrect number of atomtypes for dihedral (4 instead of 2 or 4)

ERROR 7 [file forcefield.itp, line 7]:
Incorrect number of atomtypes for dihedral (4 instead of 2 or 4)

ERROR 8 [file forcefield.itp, line 8]:
Incorrect number of atomtypes for dihedral (4 instead of 2 or 4)

ERROR 9 [file forcefield.itp, line 9]:
Incorrect number of atomtypes for dihedral (2 instead of 2 or 4)

ERROR 10 [file forcefield.itp, line 10]:
Incorrect number of atomtypes for dihedral (0 instead of 2 or 4)

Program: gmx grompp, version 2023.5
Source file: src/gromacs/gmxpreprocess/topio.cpp (line 612)

Fatal error:
Syntax error - File forcefield.itp, line 17
Last line read:
‘1 2 yes 0.5 0.8333’
Found a second defaults directive.