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Lubin
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I felt that there couldn’t be such an isogeny, but when I saw @DavidLoefflere’s answer, I realized that I had an argument, too. The formal group of the elliptic curve would be of height two, defined over $\mathbb Z_p$, but such things don’t have $p$-isogenies: the quotient formal group is definable only over a suitably ramified extension.

Lubin
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