Didn’t wash my torrentshell 3L for a few months of use, how can I restore waterproofing

I live in a very wet area, and have worn my 3L for probably 3months in the 8mins ha I’ve had it. I also completely forgot you are meant to regularly wash it to maintain waterproofing. I washed it recently as per recommendations, with pure soap and tumble dried, yet not much of the original waterproofing power returned, how can this be fixed?