Update interval

Hello,

my client purchased the pro version.
i first set the update interval time to 15 mins it was working fine for approx 2 months suddenly all my feed sources were showing “next update in None”.
so i reset the aggregator settings, all works fine but i am oblige to set the interval to 1hour. 5 – 10 & 15 mins are missing from update interval list.

Plz advise as i need to set it to 15mins.

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