Oscillations in poshold and land mode after a successful autotune

Hello, my setup is as follows:
Cube orange Plus flight controller with Here 3+ GPS
Tarot T960 hexa drone frame
T-motor MN4014 400KV motors and Hobbywing Skywalker 60A esc
1755 Carbon Fiber propellers
16000 mah 15C lipo Battery 6S
I followed all the initial tuning process and configured the Harmonic notch filter as well. After that I moved onto the Autotune procedure and achieved good results from the process in alt hold mode.

I took some test flights after autotune. Took off in alt hold and put the drone in pos hold. As soon as the mode switch, the drone demonstrated high levels of oscillations. Further, I put the drone in land mode to safely end the flight but the oscillations extended to land mode as well.

I am attaching the log file of the above described flight for reference. Please help me out on how to remove osicllations while maintaining similar level of tight response from the drone that i received after autotune.
Log file: https://drive.google.com/file/d/1WFXWcNBPjMZ3sRd1l0G9sFjks_Vfo9_s/view?usp=share_link
Thank You

Motor outputs are “noisy” and sometimes hitting minimum while maintaining stability.
There’s three different (but slightly related) actions I’d take to soften that shaky attitude control.

It looks like the in-flight FFT is targeting the wrong frequency. I think you can change over to throttle-based harmonic notch filtering and simplify things

ATC_THR_MIX_MAX,0.5 // keep this at 0.5 unless you have a specific need to increase it
FFT_ENABLE,0  // disbale in-flight FFT
INS_ACCEL_FILTER,10
INS_HNTC2_ENABLE,0 // disable the 2nd notch filter
INS_HNTCH_BW,25
INS_HNTCH_FM_RAT,0.7
INS_HNTCH_FREQ,50
INS_HNTCH_HMNCS,3
INS_HNTCH_MODE,1
INS_HNTCH_OPTS,0
INS_LOG_BAT_MASK,1
INS_LOG_BAT_OPT,4

Reduce the PIDs a bit, at least until stability is confirmed and Autotune can be rerun.

ATC_ANG_PIT_P,10.0
ATC_ANG_RLL_P,7.0
ATC_ANG_YAW_P,7.0
ATC_RAT_PIT_D,0.008
ATC_RAT_PIT_I,0.16
ATC_RAT_PIT_P,0.16
ATC_RAT_RLL_D,0.0125
ATC_RAT_RLL_I,0.25
ATC_RAT_RLL_P,0.25

I’ve selected values proportionally lower that your original values, and reduced D terms a little more which will hopefully take out a lot of the little higher frequency shakes.

Definitely set up the battery voltage monitoring, and current too if you can
otherwise these have no effect
MOT_BAT_VOLT_MAX and MIN
and you cant go on for long without the correct battery failsafe settings and actions - an unexpected battery issue catches out nearly everyone.
Then set these:

BATT_ARM_VOLT,22.10
BATT_CRT_VOLT,21.00
BATT_LOW_VOLT,21.60
BATT_FS_CRT_ACT,1
BATT_FS_LOW_ACT,2 or 3

Do a new test flight in AltHold and if everything is going Ok switch to Loiter (poshold is old and Loiter is so much better)
Let’s see that .bin log file!