Problem in predict.fregre.fd function: could not find function "is.na.fdata"

Hi can anyone help me please in understanding this error? I can give all the info if needed!

My guess would be not loading a library/package.

Otherwise...

I think its needed.

I was able to confirm that this works:

(require(fda.usc))

fda.usc:::is.na.fdata(fdata(iris))

Is that a function? if yes can you send a link please?

Its a function in package far