Large number of imaginary frequencies with ROKS and del SCF

Questions
#1

Hello, I performed a singlet excited-state (S1) geometry optimization using ROKS and del SCF approach. The optimization converged smoothly in a few cycles with small gradients, However, when I performed a frequency calculation at the optimized geometry, I obtained many imaginary frequencies. I previously did this with TDDFT approach but did not face this issue. How can I resolve it?
Input file with ROKS:
$molecule
0 1
H 1.3292676 -1.6836893 -3.0809952
C 0.7356205 -0.9500791 -3.6169987
C 0.0000000 0.0000000 -2.8999730
C -0.7356205 0.9500791 -3.6169987
H -1.3292676 1.6836893 -3.0809952
C -0.7357354 0.9503581 -5.0068087
H -1.3188870 1.6920649 -5.5435948
C 0.0000000 0.0000000 -5.7078619
H 0.0000000 0.0000000 -6.7931470
C 0.7357354 -0.9503581 -5.0068087
H 1.3188870 -1.6920649 -5.5435948
C 0.0000000 0.0000000 -1.4156563
C -0.0005202 1.1978303 -0.6937517
C 0.0005202 1.1978303 0.6937517
C 0.0000000 0.0000000 1.4156563
C -0.0005202 -1.1978303 0.6937517
C 0.0005202 -1.1978303 -0.6937517
C 0.0000000 0.0000000 2.8999730
C 0.7356205 0.9500791 3.6169987
C 0.7357354 0.9503581 5.0068087
C 0.0000000 0.0000000 5.7078619
C -0.7357354 -0.9503581 5.0068087
C -0.7356205 -0.9500791 3.6169987
H 0.0109345 2.1444854 -1.2243742
H -0.0109345 2.1444854 1.2243742
H 0.0109345 -2.1444854 1.2243742
H -0.0109345 -2.1444854 -1.2243742
H 1.3292676 1.6836893 3.0809952
H 1.3188870 1.6920649 5.5435948
H 0.0000000 0.0000000 6.7931470
H -1.3188870 -1.6920649 5.5435948
H -1.3292676 -1.6836893 3.0809952
$end

$rem
JOB_TYPE SP
METHOD CAMB3LYP
BASIS 6-31G(d,p)
SCF_CONVERGENCE 8
MAX_SCF_CYCLES 200
SYM_IGNORE TRUE
SOLVENT_METHOD PCM
MEM_TOTAL 248000
MEM_STATIC 4000
$end

$pcm
THEORY CPCM
method swig
radii bondi
solver inversion
$end

$solvent
DIELECTRIC 37.5
OPTICALDIELECTRIC 1.8068
$end

@@@

$molecule
read
$end

$comment
OPP S1 Delta-SCF (HOMO->LUMO) in MeCN PCM
$end

$rem
JOB_TYPE OPTIMIZATION
METHOD CAMB3LYP
BASIS 6-31G(d,p)
UNRESTRICTED FALSE
ROKS TRUE
SCF_GUESS READ
SCF_CONVERGENCE 6
MAX_SCF_CYCLES 200
SYM_IGNORE TRUE
SOLVENT_METHOD PCM
MEM_TOTAL 248000
MEM_STATIC 4000
$end

$pcm
THEORY CPCM
method swig
radii bondi
solver inversion
$end

$solvent
DIELECTRIC 37.5
OPTICALDIELECTRIC 1.8068
$end

$occupied
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 62
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61
$end

@@@

$molecule
read
$end

$comment
OPP S1 Delta-SCF (HOMO->LUMO) in MeCN PCM
$end

$rem
JOB_TYPE Frequency
METHOD CAMB3LYP
BASIS 6-31G(d,p)
UNRESTRICTED FALSE
ROKS TRUE
SCF_GUESS READ
SCF_CONVERGENCE 6
MAX_SCF_CYCLES 200
SYM_IGNORE TRUE
SOLVENT_METHOD PCM
MEM_TOTAL 248000
MEM_STATIC 4000
$end

$pcm
THEORY CPCM
method swig
radii bondi
solver inversion
$end

$solvent
DIELECTRIC 37.5
OPTICALDIELECTRIC 1.8068
$end

Input file with del SCF:
$molecule
0 1
H 1.3292676 -1.6836893 -3.0809952
C 0.7356205 -0.9500791 -3.6169987
C 0.0000000 0.0000000 -2.8999730
C -0.7356205 0.9500791 -3.6169987
H -1.3292676 1.6836893 -3.0809952
C -0.7357354 0.9503581 -5.0068087
H -1.3188870 1.6920649 -5.5435948
C 0.0000000 0.0000000 -5.7078619
H 0.0000000 0.0000000 -6.7931470
C 0.7357354 -0.9503581 -5.0068087
H 1.3188870 -1.6920649 -5.5435948
C 0.0000000 0.0000000 -1.4156563
C -0.0005202 1.1978303 -0.6937517
C 0.0005202 1.1978303 0.6937517
C 0.0000000 0.0000000 1.4156563
C -0.0005202 -1.1978303 0.6937517
C 0.0005202 -1.1978303 -0.6937517
C 0.0000000 0.0000000 2.8999730
C 0.7356205 0.9500791 3.6169987
C 0.7357354 0.9503581 5.0068087
C 0.0000000 0.0000000 5.7078619
C -0.7357354 -0.9503581 5.0068087
C -0.7356205 -0.9500791 3.6169987
H 0.0109345 2.1444854 -1.2243742
H -0.0109345 2.1444854 1.2243742
H 0.0109345 -2.1444854 1.2243742
H -0.0109345 -2.1444854 -1.2243742
H 1.3292676 1.6836893 3.0809952
H 1.3188870 1.6920649 5.5435948
H 0.0000000 0.0000000 6.7931470
H -1.3188870 -1.6920649 5.5435948
H -1.3292676 -1.6836893 3.0809952
$end

$rem
JOB_TYPE SP
METHOD CAMB3LYP
BASIS 6-31G(d,p)
SCF_ALGORITHM DIIS
SCF_CONVERGENCE 8
MAX_SCF_CYCLES 200
SYM_IGNORE TRUE
UNRESTRICTED TRUE
SOLVENT_METHOD PCM
MEM_TOTAL 248000
MEM_STATIC 4000
$end

$pcm
THEORY CPCM
method swig
radii bondi
solver inversion
$end

$solvent
DIELECTRIC 37.5
OPTICALDIELECTRIC 1.8068
$end

@@@

$molecule
read
$end

$rem
JOB_TYPE OPTIMIZATION
METHOD CAMB3LYP
BASIS 6-31G(d,p)
UNRESTRICTED TRUE
OPSING TRUE
MOM_START TRUE
MOM_METHOD MOM
SCF_ALGORITHM DIIS
SCF_GUESS READ
SCF_CONVERGENCE 6
MAX_SCF_CYCLES 500
SOLVENT_METHOD PCM
SYM_IGNORE TRUE
MEM_TOTAL 248000
MEM_STATIC 4000
$end

$pcm
THEORY CPCM
method swig
radii bondi
solver inversion
$end

$solvent
DIELECTRIC 37.5
OPTICALDIELECTRIC 1.8068
$end

$occupied
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 62
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61
$end

@@@

$molecule
read
$end

$rem
JOB_TYPE Frequency
METHOD CAMB3LYP
BASIS 6-31G(d,p)
UNRESTRICTED TRUE
OPSING TRUE
MOM_START TRUE
MOM_METHOD MOM
SCF_ALGORITHM DIIS
SCF_GUESS READ
SCF_CONVERGENCE 6
MAX_SCF_CYCLES 500
SOLVENT_METHOD PCM
SYM_IGNORE TRUE
MEM_TOTAL 248000
MEM_STATIC 4000
$end

$pcm
THEORY CPCM
method swig
radii bondi
solver inversion
$end

$solvent
DIELECTRIC 37.5
OPTICALDIELECTRIC 1.8068
$end