ESP8266 connect problem, Login timeout

I have a stand alone ESP8266 ESP-07 which no longer will connect.
I worked fine a long time and suddenly it started with this problem.
This is the serial output after reset:

Connecting to WiFi
[38334] Connecting to Harbeck_2
[38838] Connected to WiFi
[38838] IP: 192.168.0.153
[38838]
___ __ __
/ _ )/ /_ _____ / /__
/ _ / / // / _ / '/
/
//_, /////_
/
__/ v0.5.4 on Arduino

[38844] Connecting to blynk-cloud.com:80
[42235] Login timeout
[44235] Connecting to blynk-cloud.com:80
[47264] Login timeout

Sometimes it will run but unconnecting all the time:
The first 3 lines are normal output from the board, reading sensors every 10 sec:
16.01.2019 17:55 Out 22.0 Alrum 22.8
16.01.2019 17:55 Out 22.0 Alrum 22.8
16.01.2019 17:55 Out 22.0 Alrum 22.8
[972770] Heartbeat timeout
16.01.2019 17:55 Out 22.0 Alrum 22.8
[975209] Connecting to blynk-cloud.com:80
[978237] Login timeout
[980237] Connecting to blynk-cloud.com:80
16.01.2019 17:56 Out 22.0 Alrum 22.8
[983879] Ready (ping: 306ms).
16.01.2019 17:56 Out 22.0 Alrum 22.8
[1002880] Heartbeat timeout
16.01.2019 17:56 Out 22.0 Alrum 22.8
[1004978] Connecting to blynk-cloud.com:80

I cannot find any help in other posts.
Does it give any meaning posting my code?

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