Hello.
SMS are sent according to the minute cron, that is, you sent an SMS, it queues up when the minute cron starts - the SMS goes to the service.
So, your problem is that the minute cron is very busy, it is running 33,361.04 s
https://prnt.sc/xrfdjpIt's about 10 o'clock, this is his last work.
What does it mean - until the cron is fully completed, it will not perform the following actions.
You need to decide something with loading, distribute the work of actions