Desperately Need Tech Help. Please

Hi
Can anyone advise me on this or give me some contact links where I can find answers.
Problem is that the game often freezes during play for at least 15 seconds, usually more.
I have the Microsoft Flight Simulator Premium Deluxe version.The recommended specs for this program are as follows :-
FS Recommended Requirement (Printed on Box)
OS Windows 10 (Nov2019 Update - 1909)
Direct X: DirectX 11
CPU Inteli5-8400- or - Ryzen 5 1500X
GPU Nvidia GTX970 or Radeon RX 590
VRAM 4GB
RAM 16 GB
HDD 150 GB
Bandwidth 20 Mbps

My computer specs are
Processor Intel(R) Core(TM) i5-8400 CPU @ 2.80GHz 2.80 GHz
Installed RAM 24.0 GB (23.9 GB usable)
System type 64-bit operating system, x64-based processor
HDD 917.16GB
Direct X Direct X 12
Bandwidth 69.65 Mbps
VRAM 8192 MB
Windows 10 Home Version 20H2
Experience Windows Feature Experience Pack 120.2212.31.0
Power Supply Berlin 630W
Display  Adaptor Radeon RX 590 series
I have tried everything including backing up my files and rebooting my computer to factory fresh.
All drivers are up to date.
Desparetly need help 
Cheers