E-mail Signature Image

Why can I no longer include an image in my e-mail signature? The image from my e-mail signature has simply been removed from my e-mail signature; it was working fine until recently. I find this very inconvenient as I no longer have the proper signature set forth by my employer. Does Apple simply want us to stop using their mail app? I may be doing things incorrectly somehow, I have tried pasting my entire signature from an e-mail I sent via desktop, but the image won't paste. I've tried downloading the image itself to my phone and pasting from there, but the "paste" option will not come up when entering my signature if what's in my clipboard is an image.