I would suggest doing some CRO on your pages that are doing well and cutting out the ones that are not working for you. If you have that many ads that are not performing I would also suggest re-targeting your ads. Maybe look at your personas/audience again and look at your goals for your ads. Make sure they're talking to the right people and solving the right problems.
Here is a list of recommendations from my website that might give you some new ideas on what could help:
If that doesn't help I would also suggest trying a site audit, you might find something you didn't see before.