(don't mind me I'm just quoting your post so I can ping you in case. I hope I'm not necroposting...)
Can you provide the BBCode for your siggy so it's easier for people to troubleshoot it? If you don't know how to do it let me know.
In case it helps, I pulled off something similar in
my About section to see if the misalignment will happen to me too. (spoiler alert: it didn't.) This is the BBCode for reference:
[CENTER][U][IMG align="left" width="100px"]https://www.belltreeforums.com/attachments/bobrocks-png.554408/[/IMG]Custom Design ID:[/U] MA-3081-8968-0954[IMG align="right" width="100px"]https://www.belltreeforums.com/attachments/bobrocks_kieran-png.554400/[/IMG]
[U]DA:[/U] DA-6834-3962-7861
[U]HHN ID:[/U] RA-1740-0176-3044
[U][IMG]https://64.media.tumblr.com/f6fe60b86b3bc64b1ffcd3ed9d7bbd8f/tumblr_inline_o19cx9sln01stmbqz_500.gif[/IMG]Discord:[/U] bobrocks20[IMG]https://64.media.tumblr.com/f6fe60b86b3bc64b1ffcd3ed9d7bbd8f/tumblr_inline_o19cx9sln01stmbqz_500.gif[/IMG]
[U]Nookipedia:[/U] BobRocks20 (inactive)
[U]Animal Crossing Community:[/U] Ki3ran (inactive)[/CENTER]