How to prevent Continuous ACK packets to my server

I found my server got continuous ACK packets from different sites, never stop, like below(I used tcpdump to capture)

1. the remote sites use https.
2. contains akamai, amazon..etc, which should be legit.

I'm wondering there are unsuccessful coections to these sites before, then this happened.

I would like to know how to not get these ACK packets.

23:12:37.555238 IP prg02s12-in-f1.1e100.net.https > 192.168.192.128.52285: Flags [FP.], seq 0, ack 1, win 64240, length 0 23:12:37.555242 IP 17.167.192.152.https > 192.168.192.128.49292: Flags [FP.], seq 0, ack 1, win 64239, length 0 23:12:37.555246 IP prg02s12-in-f14.1e100.net.https > 192.168.192.128.49961: Flags [FP.], seq 0:55, ack 1, win 64240, length 55 23:12:37.555253 IP 17.164.1.38.https > 192.168.192.128.49844: Flags [FP.], seq 0:37, ack 1, win 64240, length 37 23:12:37.555293 IP a2-16-84-128.deploy.akamaitechnologies.com.https > 192.168.192.128.49850: Flags [FP.], seq 0:31, ack 1, win 64240, length 31 23:12:37.555301 IP 125.209.252.12.https > 192.168.192.128.49929: Flags [FP.], seq 0, ack 1, win 64240, length 0 23:12:37.555307 IP prg02s12-in-f4.1e100.net.https > 192.168.192.128.49964: Flags [FP.], seq 0:55, ack 1, win 64240, length 55 23:12:37.655195 IP fra07s31-in-f1.1e100.net.https > 192.168.192.128.58291: Flags [FP.], seq 0, ack 1, win 64240, length 0 23:12:37.655227 IP ec2-54-193-107-210.us-west-1.compute.amazonaws.com.https > 192.168.192.128.50448: Flags [FP.], seq 0:7, ack 1, win 64240, length 7 23:12:37.655233 IP fra07s31-in-f1.1e100.net.https > 192.168.192.128.41618: Flags [FP.], seq 0:110, ack 1, win 64240, length 110 23:12:37.655238 IP ec2-54-154-38-161.eu-west-1.compute.amazonaws.com.5223 > 192.168.192.128.48941: Flags [FP.], seq 0:7, ack 1, win 64240, length 7 23:12:37.655243 IP fra07s31-in-f1.1e100.net.https > 192.168.192.128.54130: Flags [FP.], seq 0:110, ack 1, win 64240, length 110 23:12:37.655247 IP prg02s12-in-f1.1e100.net.https > 192.168.192.128.52285: Flags [FP.], seq 0, ack 1, win 64240, length 0 23:12:37.655254 IP 17.167.192.152.https > 192.168.192.128.49292: Flags [FP.], seq 0, ack 1, win 64239, length 0 23:12:37.655259 IP prg02s12-in-f14.1e100.net.https > 192.168.192.128.49961: Flags [FP.], seq 0:55, ack 1, win 64240, length 55 23:12:37.655265 IP 17.164.1.38.https > 192.168.192.128.49844: Flags [FP.], seq 0:37, ack 1, win 64240, length 37 23:12:37.655271 IP a2-16-84-128.deploy.akamaitechnologies.com.https > 192.168.192.128.49850: Flags [FP.], seq 0:31, ack 1, win 64240, length 31 23:12:37.655275 IP 125.209.252.12.https > 192.168.192.128.49929: Flags [FP.], seq 0, ack 1, win 64240, length 0 23:12:37.655281 IP prg02s12-in-f4.1e100.net.https > 192.168.192.128.49964: Flags [FP.], seq 0:55, ack 1, win 64240, length 55