Little background:
Working for a tech company as Support and Trainer. They increased my salary by less than 10% for my promotion to Trainer and don't want to increase my wage for fulfilling two jobs, going so far as to claim the reason for the denied raise was that I worked two jobs, and somehow I wasn't able to do 100% of either, justifying underpayment. Insane. I also recently onboarded a 3rd party company that would be doing 300% more installs than us, directly feeding our revenue stream. No bonus. Nothing.
I'm already making 20-30% less than entry level positions in the same field. I've got an interview next week and I'm just so ready to pull the trigger and tell my company they need to pay up or I'm leaving. I don't have experience with this, but I've drafted a long letter outlining my duties and grievances. Just looking for some advice. I'm starting to feel undervalued and I am growing angst towards my employer. I'd like to avoid as much toxicity as possible.