Many have already posted that this is completely normal and I agree with that.
I’d advise you to NEVER accelerate monster chests. Certainly not for 20 gems (which is a full 12 hour skip for anyone who doesn’t know), but I’d say not for any number of gems. The rewards just don’t justify it.
On the other hand, I think accelerating Raid Chests (assuming you’re opening them in the Diamond Arena), can be a reasonable proposition, depending on the gem cost and how quickly you fill them / how many you can fill in a day. I don’t mean this disparagingly, but based on your level that is probably not a great use of resources.
I hope you can take this in the constructive way in which I intend it, listen, take it seriously, and find a way to implement it into your gameplay.