Hey, @mohsen2677!
To confirm, the issue is that the variable product shows the sale price, but it does not show the original price too, as the simple product does, right?
If I understood this correctly, please note that this is working as expected. By default, variable products do not show the original price, only the sale price.
I found a enhancement request for this to be implemented here.
We cannot guarantee it will be implemented, but I suggest commenting on the GitHub report to show more users have interest in this feature ??
I hope this was clarifying.
Please let us know if there’s anything else we can do to help or if you have any questions.
Have a wonderful day!