Blynk login failed

I get continuously connected and disconnected to/from blynk cloud server.
When the blynk app is not active, then there are no interruptions.
As soon as I bring the app to foreground, then countinuously disconnecting

there are two sections in the log
1)

[Jan 24 18:54:14.300] mgos_blynk.c:57         BLYNK SEND type 6, id 53, len 0
[Jan 24 18:54:14.393] mgos_blynk.c:101        BLYNK STATUS: type 0, len 5 rlen 200
[Jan 24 18:54:14.397] mgos_blynk.c:106        BLYNK LOGIN SUCCESS, setting ping timer
[Jan 24 18:54:27.631] mgos_blynk.c:57         BLYNK SEND type 20, id 36, len 16
[Jan 24 18:54:27.724] mgos_blynk.c:101        BLYNK STATUS: type 0, len 5 rlen 2
[Jan 24 18:54:27.727] mgos_blynk.c:109        BLYNK LOGIN FAILED
[Jan 24 18:54:27.733] mgos_blynk.c:167        BLYNK DISCONNECT

in both cases len is 5, but in second case rlen is 2 instead of 200.
Is it getting somehow cut-off?
Any ideas?

Full log:

[Jan 24 18:54:12.290] mgos_blynk.c:106        BLYNK LOGIN SUCCESS, setting ping timer
[Jan 24 18:54:14.300] mgos_blynk.c:57         BLYNK SEND type 6, id 53, len 0
[Jan 24 18:54:14.393] mgos_blynk.c:101        BLYNK STATUS: type 0, len 5 rlen 200
[Jan 24 18:54:14.397] mgos_blynk.c:106        BLYNK LOGIN SUCCESS, setting ping timer
[Jan 24 18:54:16.405] mgos_blynk.c:57         BLYNK SEND type 6, id 54, len 0
[Jan 24 18:54:16.501] mgos_blynk.c:101        BLYNK STATUS: type 0, len 5 rlen 200
[Jan 24 18:54:16.503] mgos_blynk.c:106        BLYNK LOGIN SUCCESS, setting ping timer
[Jan 24 18:54:18.512] mgos_blynk.c:57         BLYNK SEND type 6, id 55, len 0
[Jan 24 18:54:18.610] mgos_blynk.c:101        BLYNK STATUS: type 0, len 5 rlen 200
[Jan 24 18:54:18.613] mgos_blynk.c:106        BLYNK LOGIN SUCCESS, setting ping timer
[Jan 24 18:54:20.622] mgos_blynk.c:57         BLYNK SEND type 6, id 56, len 0
[Jan 24 18:54:20.724] mgos_blynk.c:101        BLYNK STATUS: type 0, len 5 rlen 200
[Jan 24 18:54:20.726] mgos_blynk.c:106        BLYNK LOGIN SUCCESS, setting ping timer
[Jan 24 18:54:22.734] mgos_blynk.c:57         BLYNK SEND type 6, id 57, len 0
[Jan 24 18:54:22.819] mgos_blynk.c:101        BLYNK STATUS: type 0, len 5 rlen 200
[Jan 24 18:54:22.822] mgos_blynk.c:106        BLYNK LOGIN SUCCESS, setting ping timer
[Jan 24 18:54:24.832] mgos_blynk.c:57         BLYNK SEND type 6, id 58, len 0
[Jan 24 18:54:24.932] mgos_blynk.c:101        BLYNK STATUS: type 0, len 5 rlen 200
[Jan 24 18:54:24.934] mgos_blynk.c:106        BLYNK LOGIN SUCCESS, setting ping timer
[Jan 24 18:54:26.943] mgos_blynk.c:57         BLYNK SEND type 6, id 59, len 0
[Jan 24 18:54:27.028] mgos_blynk.c:101        BLYNK STATUS: type 0, len 5 rlen 200
[Jan 24 18:54:27.030] mgos_blynk.c:106        BLYNK LOGIN SUCCESS, setting ping timer
[Jan 24 18:54:27.622] mgos_blynk.c:101        BLYNK STATUS: type 20, len 9 rlen 4
[Jan 24 18:54:27.624] mgos_blynk.c:120        BLYNK HW: vr 1
[Jan 24 18:54:27.631] mgos_blynk.c:57         BLYNK SEND type 20, id 36, len 16
[Jan 24 18:54:27.724] mgos_blynk.c:101        BLYNK STATUS: type 0, len 5 rlen 2
[Jan 24 18:54:27.727] mgos_blynk.c:109        BLYNK LOGIN FAILED
[Jan 24 18:54:27.733] mgos_blynk.c:167        BLYNK DISCONNECT
[Jan 24 18:54:29.143] mongoose.c:3142         0x3ffef6e4 blynk-cloud.com:8442 -,-,-
[Jan 24 18:54:29.146] mongoose.c:3142         0x3fff4734 udp://192.168.137.1:53 -,-,-
[Jan 24 18:54:29.151] mongoose.c:3012         0x3fff4734 udp://192.168.137.1:53
[Jan 24 18:54:29.157] mongoose.c:3026         0x3fff4734 udp://192.168.137.1:53 -> 0
[Jan 24 18:54:29.179] mongoose.c:3012         0x3ffef6e4 tcp://139.59.206.133:8442
[Jan 24 18:54:29.286] mongoose.c:3026         0x3ffef6e4 tcp://139.59.206.133:8442 -> 0
[Jan 24 18:54:29.292] mgos_blynk.c:144        BLYNK CONNECT
[Jan 24 18:54:29.295] mgos_blynk.c:57         BLYNK SEND type 2, id 1, len 32
[Jan 24 18:54:29.387] mgos_blynk.c:101        BLYNK STATUS: type 0, len 5 rlen 200
[Jan 24 18:54:29.390] mgos_blynk.c:106        BLYNK LOGIN SUCCESS, setting ping timer
[Jan 24 18:54:31.398] mgos_blynk.c:57         BLYNK SEND type 6, id 60, len 0
[Jan 24 18:54:31.484] mgos_blynk.c:101        BLYNK STATUS: type 0, len 5 rlen 200
[Jan 24 18:54:31.487] mgos_blynk.c:106        BLYNK LOGIN SUCCESS, setting ping timer
[Jan 24 18:54:32.633] mgos_blynk.c:101        BLYNK STATUS: type 20, len 9 rlen 4
[Jan 24 18:54:32.635] mgos_blynk.c:120        BLYNK HW: vr 1
[Jan 24 18:54:32.641] mgos_blynk.c:57         BLYNK SEND type 20, id 36, len 16
[Jan 24 18:54:33.496] mgos_blynk.c:57         BLYNK SEND type 6, id 61, len 0
[Jan 24 18:54:34.303] mgos_blynk.c:101        BLYNK STATUS: type 0, len 5 rlen 2
[Jan 24 18:54:34.306] mgos_blynk.c:109        BLYNK LOGIN FAILED
[Jan 24 18:54:34.312] mgos_blynk.c:167        BLYNK DISCONNECT
[Jan 24 18:54:35.143] mongoose.c:3142         0x3fff487c blynk-cloud.com:8442 -,-,-
[Jan 24 18:54:35.145] mongoose.c:3142         0x3fff46b4 udp://192.168.137.1:53 -,-,-
[Jan 24 18:54:35.152] mongoose.c:3012         0x3fff46b4 udp://192.168.137.1:53
[Jan 24 18:54:35.157] mongoose.c:3026         0x3fff46b4 udp://192.168.137.1:53 -> 0
[Jan 24 18:54:35.180] mongoose.c:3012         0x3fff487c tcp://139.59.206.133:8442
[Jan 24 18:54:35.273] mongoose.c:3026         0x3fff487c tcp://139.59.206.133:8442 -> 0
[Jan 24 18:54:35.278] mgos_blynk.c:144        BLYNK CONNECT
[Jan 24 18:54:35.280] mgos_blynk.c:57         BLYNK SEND type 2, id 1, len 32
[Jan 24 18:54:35.358] mgos_blynk.c:101        BLYNK STATUS: type 0, len 5 rlen 200
[Jan 24 18:54:35.360] mgos_blynk.c:106        BLYNK LOGIN SUCCESS, setting ping timer
[Jan 24 18:54:37.370] mgos_blynk.c:57         BLYNK SEND type 6, id 62, len 0
[Jan 24 18:54:37.455] mgos_blynk.c:101        BLYNK STATUS: type 0, len 5 rlen 200
[Jan 24 18:54:37.458] mgos_blynk.c:106        BLYNK LOGIN SUCCESS, setting ping timer
[Jan 24 18:54:39.467] mgos_blynk.c:57         BLYNK SEND type 6, id 63, len 0
[Jan 24 18:54:39.555] mgos_blynk.c:101        BLYNK STATUS: type 0, len 5 rlen 200
[Jan 24 18:54:39.557] mgos_blynk.c:106        BLYNK LOGIN SUCCESS, setting ping timer
[Jan 24 18:54:41.566] mgos_blynk.c:57         BLYNK SEND type 6, id 64, len 0
[Jan 24 18:54:41.644] mgos_blynk.c:101        BLYNK STATUS: type 0, len 5 rlen 200
[Jan 24 18:54:41.647] mgos_blynk.c:106        BLYNK LOGIN SUCCESS, setting ping timer

hm, it works now…
I had a display which was reading every 5 seconds or so.
When I removed it from Blynk it worked.