Azure and assure are easily confused words.
The spell-check application of most word processing software programs would not catch a slip-up of these two words. Spell-check is looking for words that aren’t in its dictionary, and words that resemble words in its dictionary but are possibly spelled wrong. Spell-check isn’t perfect. It doesn’t know and can’t guess what word you wanted or what word you meant, it can only judge the words on the page. If you used words that are all spelled correctly, it gives you a pass anyway.
Autocorrect suggests words that start with the same letters. It’s suggesting what word you may want to save time, but quite often, its suggestions are pretty off base. They don’t help you out, but they do make you laugh.
Azure is an adjective. It describes objects with a blue color, like the sky.
Assure is a verb. It means to provide information in a positive, encouraging tone or manner. For legal or other documents, assuring involves using authoritative language that pledge, promise that the agreement or proposal is solid and most likely will not fail.
The following story uses both words correctly:
Azizi was anxious about her upcoming outdoor wedding. The venue owners and local meterologist assured her that the third Saturday in September would be a comfortably cool day under a clear, azure sky.