What would you do for a company that you bought at a high price but you feel is a solid company?

I bought Google at 2500 roughly. I feel like it's going to go down to the 2000 range. Shopify avg is 620. They are now at 450 roughly. Nvidia 180 but I think NVidia is going to continue going down regardless of how profitable and how good they are. Would you simply buy more to lower your cost average? Just curious. I've also been doing this with Starbucks. I did this with Target and now I'm being rewarded nicely.

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With companies that are strong and pay dividends, I feel good buying more because I will be getting paid regardless. Thanks in advance!