Some people just can't tolerate Beta blockers. Speak to your GP they might be able to change your meds.
I have taken 7.5mg of Bisoprolol, now on 5mg, I also take Apixaban, plus Amiodarone for my AF... (had an Ablation 4 weeks ago) advise they will be stopped or Reduced in a few months.
I have never had an issues or fatigue, with Beta Blocker's.
Amiodarone is know as an unpleasant Drug, that's a different story.
Beta blockers are world wide known successful Drug, only a small number of folk can't take them.
Your Doctors did the correct thing, you just have had an unfortunate experience, millions take them with no issue.