Issue bcmath present but not found

[WhiteTiger]

When installing an application with Softaculous, I get this error:
The following errors were found :
Required PHP extension not found : bcmath

The domain is with php7.4 in fpm and in Tools & Settings / PHP Settings I see that the "bcmath" checkbox is checked. This also applies to other PHP configurations.
So, what should I do?
Tanks.

 

[pleskpanel]

hmmm...

Everyone raised their hands at once on this one - A bit obscure but have you read into this?

 

[WhiteTiger]

I have read it, but I don't understand why I have to install it again if it is already recognized in the Plesk configuration panels.
In any case, when I ask to install php-bcmath I am prompted to install php7.3-bcmath.
Instead, if I ask to install php7.4-bcmath I get the error "Unable to locate package php7.4-bcmath"