Cellular Data Issues with IPhone 12 Pro Max

I’ve been using my iPhone 12 Pro Max for 4 days now , however I have been having issues with the cellular data , the data keeps dropping every 10-15 seconds and that’s when my connection cuts out and comes back on its very annoying and is affecting my work and things I do on my phone I already reset the network settings and it’s till the same issue , it’s not my sim card because the 8plus I was using just before wasn’t having these issues . I need this issue to be resolved please ASAP.