Penis soreness from lots of teasing

My husband and I are fairly new to male chastity. We’re currently in the midst of our longest denial period yet. He gets edged frequently, sometimes multiple times a day. Although we use plenty of water-based lubricant, it doesn’t seem to be doing the trick. This has led to some pretty bad soreness on his penile skin. Is there a solution? (Obviously cutting back on the teasing would help, but where’s the fun in that?) Any ideas?