Issue with blocking from the baseline

Soften your grip or take it after the back glass

If the serve is really fast, block it with the racket slightly tilted so it goes up, or if it’s really hard, wait for it to come from the glass so you can play the ball softer with more control.

You sure you are just blocking? Blocking means minimal amount of swing and I find it hard to believe that with that minimum swing, a return will fly over all the way to opponent's back glass. If you are full swinging instead of blocking, reduce your backswing if you don't want it to fly all the way behind. If it is low and fast, crouch low, step in so body become sideways, open your racquet face around 20-30 degree and just rotate your body instead of swinging your arm. Stiffen the arm and wrist. Make sure to have compact movement so you can accurately hit the sweetspot. You don't need a lot of power to return a fast one. You need accuracy for that sweetspot. Done correctly, you will easily return that fast energy back to your opponent.

With a hard serve unless you're trying to be tricky then try to reduce your swing and think more about blocking whilst rolling your body weight forward as you hit. You barely even need to swing and it'll also usually help with pace and power

Agreed with the folks saying play it off the glass, that's my tactic

How is your feet positioning? You should be facing the side and getting low and under the ball to return it. Try to hit the ball before it makes contact with the glass if its past the base line.

You are probably trying to lob fast or sliced serves and the ball goes out because it's not controlled. If the serve is difficult, wait for it to bounce so that it slows down. If it's so sliced that it dies right after the glass, take a step forward and take it before. Try not to block but hit a flat groundstroke that either goes close to the net or falls right behind (Chiquita).

Also try returning straight back to the server, he will have less time to respond than his partner who is just waiting for the ball. You want to try and hit the ball as low over the net as possible when returning with force. This gives your ball the best chance of dipping after the net and bouncing before hitting the glass. You could also try slicing the ball to take some pace off it and keep the return as low as possible over the net. This is a great option because when you slice the ball, you put a reverse spin on the ball and it is harder to return. The other advantage of slicing the ball to put a reverse spin on it is that after it bounces on the ground and then hits the glass, the trajectory of the bounce from the glass is downward, again making it harder to return.