I know it is some form of する。The context is this tweet:
いいえ!無視は しちゃい けませんな(^-^)/気持ちは受け取って♪(´ε` )RT @PuyoPuyoStar: @shinji_sid すみません。先程ツイート送ったんですが、「無理してはいけません」と書きたかったところ、「無視してはいけません」と書いてしまいました。本当すみませ
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Sign up to join this communityI think you're just misreading the the sentence slightly - it should be split as:
無視は しちゃ いけませんな
It's bad to ignore it, right?
しちゃ is a shortened form of しては, as far as I remember. In this particular case it seems to me an odd sentence, purely because of the emphasis placed on the 無視 by the は. The sentence that I'd usually expect would be something like
先生を無視しちゃいけませんな
or in a slightly less shortened (and more polite) way,
先生を無視してはいけませんね