Sertraline is a medication that needs very gradual withdrawal to avoid symptoms. Missing a dose is varna teed to make you feel really bad.
I don't know what dose you are on, but it is never a good idea to come off without working with the prescriber. They may be able to give you smaller tablets and if it's the right preparation you might be able to cut them in half.

If, for example, you were taking 200mg, then reducing by 50 or even 25 mg for at least a week may be a good rate, then reduce a little more. You may find it beneficial to reduce even slower.

As an example, when I came off amitriptyline I had been on 250mg for some years. To avoid withdrawal symptoms I had to drop 25mg ONE day n every FOUR for a week, then alternate days, then 3 days in 4. That way it took four weeks to reduce by 25mg. It was slow, but I came off it successfully, with no significant withdrawal symptoms and stayed antidepressant free for several years.

I hope this is a helpful idea to help you withdraw without problems. Most doctors encourage people to come off more quickly, but sometimes it helps to come off meds super slowly so your body has time to adjust.

Best wishes and good luck.