is anyone on here a vet tech?

Posting this here on the off chance someone works with animals and can help me out. This appeared on my dogs lip about a week ago. Doesn't seem to be getting any better. I've been trying to keep it clean by dabbing it with a bit of peroxide 2x a day. 
Anyone know what it may be or how to get rid of it?
We're not positive but we believe she is a hound/Springer mix

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