My credit is disappearing

[Nonameson1]

(18 October 2020) From Three: Thanks for topping up using AIB Internet Banking. Your new balance is 93.8 EUR. Check options at www.three.ie/my3

(18 November 2020) From Three: Thanks for topping up using AIB Internet Banking. Your new balance is 74.23 EUR. Check options at www.three.ie/my3

Today I topped up after I got this message:
From Three: Your balance is low. Check options at www.three.ie/my3

Why can’t three send messages consistently at the same time instead of waiting for the credit to run out. Which maybe is the case, but could you check why credit is running so low, when I am still within the 28 day period.

[LauraH]

@Nonameson1 Hi there 👋 I'm wondering if previous credits have expired. Did you know that when you top-up your credit will remain active on your balance for 180 days? Each top-up has its own expiry date and if you make a chargeable call your 180 days starts from that time?