Sold covered puts expiration clarification

Hi All,

Last week on Robinhood, I had sold $5 puts (cash secured) on AMC expiring 7/21. On this date, the stock price at closing was $4.40 and after closing on Friday on Robinhood it said that I was pending the purchase of the shares at $5 each and showed under my positions. AMC then went up a lot after hours. Then today I check my account again and the pending shares are gone, they didn't buy me the shares at $5 each. Is this how this should work for my sold puts? Or am I entitled to have bought these for $5 each as the closing price was at $4.40 regardless of the afterhour price action? Any insight would be appreciated, thank you!