I went looking for dw_straybunnies prompts, and found 'Jackie Tyler / Lucie Miller / in the end'. A few hours later, there was this.
The Blockage (1957 words) by JohnAmendAll
[Also available at Teaspoon]
Fandom: Doctor Who (2005), Doctor Who (Big Finish Audio)
Rating: General Audiences
Warnings: No Archive Warnings Apply
Characters: Jackie Tyler, Lucie Miller
Summary: Jackie calls the plumber to deal with a blocked drain. But it isn't her usual man who comes round.