Problem connecting Huawei Y3ii handphone to router WR841N v8

Problem connecting Huawei Y3ii handphone to router WR841N v8
Problem connecting Huawei Y3ii handphone to router WR841N v8
2018-06-15 23:24:26
Model : WR841N

Hardware Version : WR841N v8 00000000

Firmware Version : 3.13.20 Build 120605 Rel.38820n


I have been using this router WR841N for a year or two without problem until recently when I bought 2 Huawei Y3ii phone which I failed to get them connected to the wifi. I seek Huawei help high and low and they blamed it on my router WR841N of Tplink. I bought two of the same type of
phone and both also cannot connect to the wifi. I bought a Nubia M2 phone, it's connection is also intermittent i.e. connected and then disconnected (its better Huawei Y3ii which can't even connect once and even if it did, it only lasted 2 seconds). Sometimes after trying many times, it would state
authentication problem. I assure you that my authentication i.e. password is definitely correct.

I have also bought a few laptops and one has initial problems of connecting to the wifi but after trying a few times, they managed to connect but occasionally they suddenly got disconnected and I have to connect again.
I have double checked all the settings and I still cannot find the solutions especially for Huawei Y3ii phone and because of that I dare not buy any new Huawei phone fearing that all Huawei phones will have problems with my TPlink router.

I did notice that about six devices including my Huawei Y3ii (based on the MAC address) are connected to the router with the status STA-ASSOC but the Huawei phone is not connected (with status "Saved, secured with WPA2") and remain unable to access the internet. Some devices are connected with status WPA2 PSK. My wireless security is set to WPA2-PSK.
If anyone knew how to solve this problem I would be very grateful for any advice given. I am on the verge of dumping this router for others.