If Protestants won't ask dead saints to intercede because there is no mediator but Jesus then why do they ask living Christians to pray for them?

Protestants reject the Catholic and Orthodox practice of asking deceased saints to pray for them, and I think there are two main reasons why they reject it: it is communicating with the dead, and it is dishonouring to Jesus. The first has been dealt with in many other questions, but I'd like to focus on the second one to see how valid an argument it is. So the second major reasons why protestants don't ask the deceased to pray for them is that they believe they need no other mediator than Jesus. For protestants, asking anyone other than Jesus to intercede with God for them is dishonouring to Jesus! But Protestant Christians have no hesitation at all in asking *living* Christians to pray for them. Why does the argument against dead Christians not apply to living Christians? If you ask your Christian brother or sister to pray for you, why is that not seeking another mediator than Jesus? The Bible clearly instructs us to pray for others, and it frequently show that early Christians asked other Christians to pray for them (ex. in Paul's letters), but does it ever instruct us to ask others to pray for us?