Muffled hearing after myringotomy & grommet insertion

I have been suffering with ear issues my entire life, and I’m now 27. I had grommets as a child, but these fell out at a young age. I now suffer with recurring Eustachian Tube Dysfunction linked with my Hay Fever. ENT recommended I go for a grommet insertion in both ears, which happened on Wednesday 1st July at 10am under general anaesthetic.

My hearing was normal going into the procedure as my hearing issues are asymptomatic. As soon as I woke up from the procedure, I noticed my hearing had become extremely muffled. I previously used the Valsalva manoeuvre to equalise the pressure, this now doesn’t do anything and all I hear is a rush of air through my ear canal. I am now some 30 hours after the procedure, how long until my hearing returns to normal?

I’ve been doing the Valsalva manoeuvre for decades now, so I have no idea what to do to get my hearing back to normal.