Try using one of the many wonderful Writing.com contests as a catalyst for completing your Contest Round entries. Many of the contests have great prompts that might inspire you.

Daily contests with prompts:
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"Daily Flash Fiction Challenge"  [13+]

October contests with prompts:
"What a Character! : Official WDC Contest"  [E] (upgraded membership or higher)
"Horror Writing Contest"  [13+]
"The Bard's Hall Contest"  [13+]