Looking for a prepaid telco plan for senior citizen

they only know how to call / receive from phone , so data plan is not that important.
need to have long validity , if possible low cost .

Any suggestion on this ?

Go for Unifi Mobile: Budget-friendly calls, but with caveats.

Pros:

1. Cheap calls: The lowest prepaid call rate at RM20 for 200 minutes (that's just RM0.10 per minute!),
and even better, it's charged by the second after the first block, saving you more.
2. Super long validity: Keep the prepaid line active for a whopping 89 days,
just by making at least one outgoing call every 89 days.

Cons to consider:

1. Active call reminder: To maintain the extended validity, remember to make a call every 89 days.
Unfortunately, the Unifi Mobile app doesn't show your expiry date,
so set calendar reminders or watch for their final 80-day warning SMS.

2. Limited reload options
Due to fewer physical dealers, topping up your prepaid account might require using your bank card through the Unifi Mobile app.
Not everyone enjoys this digital-only approach.

Unifi prepaid mobile, non expiry dates as long there is usage (call/sms/data) within every 90days

Or

Xox prepaid, 36 months validity for new user/mnp. Can buy 6 months or 1 year validity. Call/sms/data are in term of season pass. So no need to worry about unused or wastage

Unifi Mobile prepaid virtually in-expiry even need not topup/buy plan.

U jist need to make a call or send an sms or use data atleast once every 90 days.

Multiple SMS reminder will be sent.
Initial reminder just advise to use to keep it active, it does not state termination date.

Just take note for further SMS reminder it will mention termination date.
That is if too lazy to keep tab the date.

U may try yoodo. Rm5 for 100 mins call. One app can rule all your yoodo number

xox is the best ..can buy longer validity & call time