Error when adding function to child theme

I’m trying to correct a typo in the dgx-donate.php file which is putting an extra space before the text:

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I tried fixing this by following the directions here and adding the dgx_donate_get_donor_section function to my child theme’s function.php file. When I did that I got the following error:

Fatal error: Cannot redeclare dgx_donate_get_tribute_section() (previously declared in \wp-content\plugins\seamless-donations\dgx-donate.php:552) in \wp-content\themes\FCNC\functions.php on line 186

Any help would be much appreciated.

Thanks!

https://ww.wp.xz.cn/plugins/seamless-donations/