I have an Issue iwith watch 6 and Iphone 7 plus.

Need help pairing an iwatch 6 with Iphone 7 plus.Says iphone out of date, yet no updates available??.Iwatch was used with Iphone 13 originally. Have reset iphone and reset watch to no avail. tried pair manually as well, will not pair.

I can buy Iphone 8 plus but will there be the same issue?

now this chat is asking me for text, what?.?