Coin Loose Inside Oem Capsule. Should I Replace Or Keep Inside Capsule?

Do you mean an Air Tite type of capsule? If so, there's no problem replacing the capsule. However, be very careful opening it so that you don't slip and damage the coin. I also use white cotton gloves so that I don't cause damage or fingerprints to the coin. Your coin isn't in the appropriately sized capsule. You can find size charts on line for specific coins and commemorative's. Measure your coin first. A local dealer should be able to help you with that as well.

There are also capsules with black rings that help with the odd-sized coins.

Here is where I purchase my coin supplies...https://www.jpscorner.com/

I have also tried "Wizard" coin supply but, they are way behind in shipping and my last order took a month.

@TinyRetreat

Not sure what you meant exactly. Did you mean to say the coin is better loose in a capsule than to replace it with a more fitted capsule?

If a coin is loose in a capsule, I'd imagine it would eventually cause wear/scratches to the surface and sides from it moving around in the capsule, would it not?

I assume it depends how often coins are being handled and if they accidentally get dropped. Some of mine are a little loose in capsule but I only look at them several times a year, don't move them from place to place so I doubt they are being damaged. Many of mine are just bullion or circulated, not high value. High value coins, I'd probably want a good capsule fit.

The first PCGS holders were not tight fits, the coins were loose inside. They are called rattlers and people collect them. I suppose if they or any coin in bigger capsule were deliberately shaken a lot it would harm them.

I think it's important to have humidity control, how they are stored, some use desiccant, dehumidifier etc.