Uniform convergence of series $\sum x/(n^p + x^2n^q)$ for $p > 1$ and $q \leq 0$

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Although a source tells me that the series $\sum\limits_{n = 1}^{\infty} \dfrac{x}{n^p + x^2 n^q}$ is not uniformly convergent for $p > 1$ and $q \leq 0$ on any interval $\left[ a, b \right]$, I have tried the following:-

We have

$$\left| \dfrac{x}{n^p + x^2 n^q} \right| = \left| \dfrac{n^{-q} x}{n^{p - q} + x^2} \right| \leq \dfrac{n^{-q} \left| x \right|}{n^{p - q}} \leq \dfrac{\max \left\lbrace \left| a \right|, \left| b \right| \right\rbrace}{n^p}$$

Now, the series $\sum\limits_{n = 1}^{\infty} \dfrac{\max \left\lbrace \left| a\ \right|, \left| b \right| \right\rbrace}{n^p}$ is convergent for $p > 1$ so that the original series is uniformly convergent by Wiestrauss M test.

Is this proof correct and the answer from the source wrong? Or is there a mistake in the proof?