My husband cheating on me?

My husband and I have been married for a year and a half. Ours is a love marriage. Recently, I discovered he has been communicating with 3-4 women he met on a dating app before we were married (we met on Tinder as well). He has been flirting with them, and even after I asked him to stop texting or calling them, he continues to do so and deletes the messages. He has also been talking with his ex, which I really dislike. Despite telling him many times to stop, he doesn't. My ex still texts me, but I don't respond because I respect my husband and our relationship. Should I start replying to my ex to make my husband jealous and understand how I feel? Any other suggestions?
My husband cheating on me?
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