@annxiuuuu
It looks like you provided a long signing reason, which could be cut off, when the signature field is positioned too far to the right, as the entire text is not able to fit on the document. This is comparable to having a stamp in a paper based scenario, where you place the stamp in a way that it does not fully stay on the document.
Moving the signature field further to the left or reducing the size may help to fit all text on the document or you could change the wording of the signing reason to be shorter.
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