clear sticky liquid from cat nipple

Hello. I am writing regarding my 4 year old cat named Kitten. She is not fixed and got out a few times during the summer. We thought she was pregnant but she never delivered and the vet checked her and said she is not pregnant. But there is still what I believe to be colostrum coming from her nipples. It has been like this for over 12 weeks. I don't know what to do.

She needs to get to the vet immediately.  Do not wait any longer.