Someone enquiring about the course explained he also had difficulty equalising. It's very common and I often get someone sitting out because of it. Here are some pointers to anyone interested, they can help prior to a diving trip and can be done on dry land.
Equalising exercises :-Try opening your jaw, and/or moving the muscles in your cheek or neck. If you can hear a clicking noise in your ears, this is your Eustachian tubes opening up. I do this combined with the normal Frenzel (pinch & blow), then it takes very little effort. I don't need to open the jaw anymore, I can keep my mouth closed and make that clicking noise by controlling muscles in my cheek &neck. I still can't equalise hands free, but can I equalise a lot better than I used to.
Practice regular dry land Equalising :-This one is good for people with bad ears. Your Eustachian tubes will get better the more you use them. They are like a lazy muscle and will become more flexible if used often and correctly. If you gently inflate and hold for 5 to 10 second and do that a few times a day should help. Note it has to be gentle and not forced. Try practicing the jaw clicking exercise from above and see if you notice a difference. This exercise is useful if you know you are going diving soon, practice the week before. Try again just before you hop in the water. Again before you duck dive.
Before the dive :-I always equalise on the surface just before I duck dive. If you can't equalise easily on the surface then don't bother trying underwater. Remember equalise often and early, it’s better to stay ahead because if you fall behind you can get “stuck” or end up getting sticky ears for later. It’s not worth pushing your ears on one dive if it means you are out the rest of the day. Or worse end up with a middle ear infection and be out for a month
This all may sound like overdoing a bit but my ears have been a limiting factor for me in competition diving. I used to struggle just to be able to equalise whilst scuba diving, I had to descend feet first on every dive. It took me time to be able to do fast descents with freediving.
Cheers,
Wal