I have the following problem:

/interface ethernet> monitor sfp2
;;; , . 2
name: sfp2
status: no-link
auto-negotiation: done
advertising:
link-partner-advertising:
sfp-module-present: yes
sfp-rx-loss: no
sfp-type: SFP-or-SFP+
sfp-connector-type: SC
sfp-link-length-9um: 20000m
sfp-vendor-name: OEM
sfp-vendor-part-number: V-S1215-S3320C
sfp-vendor-revision: A
sfp-vendor-serial: V1703220083
sfp-manufacturing-date: 17-03-23
sfp-wavelength: 1550nm
sfp-temperature: 61C
sfp-supply-voltage: 3.234V
sfp-tx-bias-current: 29mA
sfp-tx-power: -6.032dBm
sfp-rx-power: -19.363dBm
eeprom-checksum: good
eeprom: 0000: 03 04 01 00 00 00 02 00 00 01 01 01 0d 00 14 c8 ........ ........
0010: 00 00 00 00 4f 45 4d 20 20 20 20 20 20 20 20 20 ....OEM
0020: 20 20 20 20 00 00 90 65 56 2d 53 31 32 31 35 2d ...e V-S1215-
0030: 53 33 33 32 30 43 20 20 41 20 20 20 06 0e 00 8b S3320C A ....
0040: 00 1a 00 00 56 31 37 30 33 32 32 30 30 38 33 20 ....V170 3220083
0050: 20 20 20 20 31 37 30 33 32 33 20 20 68 b0 01 93 1703 23 h...
0060: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ........ ........
0070: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ........ ........
0080: 5a 00 d8 00 55 00 dd 00 8c a0 6d 60 88 b8 71 48 Z...U... ..m`..qH
0090: af c8 01 f4 9c 40 03 e8 27 10 02 77 1f 07 03 1a .....@.. '..w....
00a0: 18 a6 00 20 13 94 00 28 ff ff ff ff ff ff ff ff ... ...( ........
00b0: ff ff ff ff ff ff ff ff 00 00 00 00 00 00 00 00 ........ ........
00c0: 00 00 00 00 3f 80 00 00 00 00 00 00 01 00 00 00 ....?... ........
00d0: 01 00 00 00 01 00 00 00 01 00 00 00 ff ff ff d9 ........ ........
00e0: 3d 1e 7e 56 39 60 09 bd 00 9b ff ff ff ff 20 00 =.~V9`.. ...... .
00f0: 00 00 00 ff 00 00 ff ff 00 00 ff 00 00 00 00 00 ........ ........


This is a connection between mikrotik CRS106-1C-5S and media convertor. "status: no-link" but sfp-rx-power: -19.363dBm
My steps:
1. I disabled "auto-negotiation" and set rate =1Gbit -> "status: link ok" but really there is no connection.
2. I changed mikrotik switch and media converter -> no result.
3. I changed sfp modules -> no result.
4. I changed SC connectors -> no result.

When i meаsure with optic meter on this fiber, the result is -18dB.
Link distance is about 400 meters.

Where to look for the problem ?