Hi Kevin

1. What is the light status of the C3150 at that time? How often it happens?

Ans: Only internet LED off, as below photo

2. With your device connected to the router directly, can you access internet?

Ans: No, We can not access the internet. But, We have confirmed the up-link port it can access the internet via the PPPoE.

3. Meanwhile, please try to access the web interface of the C3150 and take a snapshot of the advanced-status page.

Ans: Only the internet has a red fork, as below (Remark: The screenshot comes on the simulator, but the screenshot is same.)

4. Besides, how do you reconnect to the internet after it lost signal?

Ans: We are trying to reboot the C3150 still not workable, then we have replugged the power still not viable(Remark:  PPPoE always not connect on the internet)

        Until firmware upgrade to version "C3150(US)_V2_170926", then redial PPPoE be able to connect on the internet.

        But....connection within 7-days... the PPPoE disconnect again....

        After reboot, the PPPoE be able to connect internet.....

Regards

GuoSyuan

Dear Kevin

Here is the advanced-status page full screenshot

Please find attached the "log.txt"

Besides, the PPPoE connection broken in the 2019-04-09, the log record as follows

===Log record =============================================

2019-04-09 05:27:06 [6] PPP: ppp2 rcvd [LCP TermReq id=0xc5]
2019-04-09 05:27:06 [3] PPP: ppp2 LCP down
2019-04-09 05:27:06 [4] PPP: ppp2 LCP down
2019-04-09 05:27:06 [6] PPP: ppp2 sent [LCP TermAck id=0xc5]
2019-04-09 05:27:10 [3] PPP: ppp2 User request
2019-04-09 05:27:10 [3] PPP: ppp2 

=========================================================

We buy the C3150 on the PCHOME(https://24h.pchome.com.tw/) in Taiwan date 2018/12/08 (four months ago), the receipt as follows.

Regards

GuoSyuan

@Kevin_Z 

I have same device and same issues here. 

Could anyone give me a hand?

It's annoying me by keep dropping couple of days.

@GuoSyuan any solution plz?