Why can I receive a 7mb video text but it is too large to forward?

Problem: I have an A51 Samsung. I can't forward a text video that was attached and text to me from another A51 (my wife's). What I tried: I tried saving smaller since I cannot trim it. It just doesn't make sense to me that my wife can attach and text me a 7 MB video but I can't do the same, having the same identical phone.