If Suretly and CrossSwap had a child, it would be this logo...

I'm not talking about plagiarism, but the resemblance between the two is evident.
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However, by searching for logo stock images, it's easy to get similar images, maybe you were just inspired by a particular style.

Here are links to some examples that are quite similar in concept.

• https://logosandtypes.com/alphabet/letter-s/british-steel-old/
• https://es.123rf.com/photo_33317500_letra-s-logo-icono-elementos-de-plantilla-de-dise%C3%B1o.html
• https://es.pngtree.com/freepng/letter-s-logo-png-vector_6616257.html