Anymore vs. Any More
These two words are the traditional expression in English and may be preferable for formal writing, particularly in a negative expression when meaning “any longer”.
I do not care for this author any more.
I do not care for this author any longer.
The two adverbs are interchangeable, and you can use them in formal and informal writing.
Dialogue is not considered a reasonable method of education anymore.
Anymore is a modern term (an evolution of any more) which may not be acceptable in the eyes of some readers. Consider your audience carefully before using this adverb.
While certain dialects may use anymore at the beginning of a sentence (Anymore one can buy anything online), this is not considered acceptable in formal writing. In fact, it’s a fairly rare usage, so you may want to remove it from your writing altogether unless you’re writing for a very specific audience.