Hello,
I don’t know if you solve the issue, but I’m posting this for others who may have the same problem!
I created a new environment in Anaconda using the command :
(conda prompt) # conda create --name tf tensorflow-gpu
Then I got the same error rescribed before… when trying to install Spyder IDE !
THE SOLUTION
I managed to solve this issue by doing these steps:

Create new anaconda environnement with python3.7 ONLY (I used Anaconda Navigator for this) => make sure to choose Python 3.7 ONLY !! => choose a name as ‘my_env’
Go to Anaconda Prompt to install separately tensoflow first then spyder.
So we need to navigate to the Python environnement that we created already (I named it my_env)

(base) # conda activate my_env
(my_env) # conda install tensorflow-gpu
(my_env) # conda install spyder

Once finished Spyder should work properly in the environment you installed it in.
Important Note:
Some packages may not be installed due to several reasons (connection problem for example…), So make sure all packages have been installed as 100% ! If not, then re-execute the same command to install all packages correctly !
Regards.
IKRAM