It's all my own fault really. Stripping away a bit of the lawn to make a seating area and putting those two raised beds in. I'm going to stab the lawn enthusiastically next year and wield a brush with lots of sharp sand and see if I can improve the drainage a bit in the damp bits. Putting up the final raised bed will get rid of the biggest puddle too but I guess that will just end up choosing the next lowest spot! Now I wish I'd stabbed the ground under the big area of weed membrane under the stony seating part as I wonder if the membrane has slowed the drainage and that's part of the issue!